Double-bonded Oxygen Research Articles

A theoretical study of the addition reactions of HF, H 2O, H 2S, NH 3 and HCN to carbodiimide and related heterocumulenes

Using ab initio methods at different levels of theory (RHF/6-31G ∗, B3LYP/6-311G ∗∗ and MP2/6-311++G ∗∗), we have investigated the reaction mechanism in gas phase of the addition of one molecule of HF, H 2O, H 2S, NH 3, and HCN to carbodiimide, carbon dioxide and ketene. In this last case both modes of addition were studied, i.e. across the carbon–carbon and the carbon–oxygen double bond. The potential energy surfaces were explored and the stationary points representing the reactants, transition states and products were localized. In all cases, the bond order and electron densities at the bond critical points were evaluated. Although our results correspond in all cases to large energy barriers for the 1:1 addition processes, these barriers are related to the results obtained using several molecules of water or ammonia.

First-Principles Theory of Muon and Muonium Trapping in the Protein Chain of Cytochrome c and Associated Hyperfine Interactions

The microscopic details of the electron transfer in cytochrome c (cyt c) are being investigated by the Muon Spin Relaxation (μSR) technique. We are using the Hartree–Fock Cluster Procedure to determine the most likely trapping sites for μ+ and muonium (Mu) in the protein chain, and have performed extensive calculations in single amino acid molecules of the protein chain of cyt c. The double-bonded oxygen atom of the carboxyl group was identified as the trapping site for both μ+ and Mu. Utilizing the wave functions we obtained from the Hartree–Fock calculations, we have determined the hyperfine field that the μ+ in Mu experiences while the latter is trapped at the oxygen.

The chemistry of Group 15 element porphyrins bearing element–carbon bonds: synthesis and properties

A variety of Group 15 element porphyrins bearing element–carbon bond(s) were synthesized mainly by use of R 3Al as an alkylating reagent. The synthetic methods, X-ray crystallographic structures, some spectral data ( 1H-NMR), and some reactions of the porphyrins were surveyed. One of the most important properties of these compounds is the formation of the element–oxygen double bond in the phosphorus and arsenic porphyrins. The bond formation was confirmed by X-ray crystallographic analysis of (OEP)P(Et)(O). The PO bond length of [(OEP)P(Et)(OH)] +Cl − and (OEP)P(Et)(O) was 1.636(4) and 1.484(9) Å, respectively (cf. PO bond length of Ph 3PO is 1.483 Å). Since (OEP)P(Et)(O) was stabilized by the formation of the PO bond, the OH proton of [(OEP)PEt(OH)] +Cl − was acidic (p K a ca. 7–8). Although the similar formation of the double bond was not observed in the corresponding antimony compounds, the corresponding AsO formation was observed in newly synthesized (OEP)As(R)(O). The relatively high acidity of the OH protons in [(OEP)M(R)(OH)] +X − (M=P, As) {and the stability of the (OEP)M(R)(O)} would be the main reason for the relatively high reactivity of phosphorus and arsenic porphyrins, [(OEP)M(R)(OH)] +X −, toward (OEP)Al(Me) to give μ-oxobridged dinuclear porphyrins and the high reactivity of phosphorus and arsenic porphyrins bearing a OOH group toward triphenylphosphine. In addition, X-ray analysis of a variety of phosphorus(V), arsenic(V), antimony(V) octaethylporphyrin (OEP) and tetraphenylporphyrin (TPP) derivatives showed the effect of the axial ligand(s) on the distortion of the porphyrin core from the plane.

Reevaluation of the Additivity Relationship for Vanadyl−Imidazole Complexes: Correlation of the EPR Hyperfine Constant with Ring Orientation

Five new vanadyl−imidazole complexes with the imidazole ring in different orientations to the vanadyl unit have been synthesized and characterized by X-ray crystallography and electron paramagnetic resonance (EPR). The hyperfine coupling constants (A∥) from the EPR spectra of these complexes were analyzed using the additivity relationship. There is some discussion as to what contribution an “aromatic imine” such as imidazole bound in the equatorial plane of a vanadyl complex makes to the hyperfine coupling. This analysis, applied to the new complexes as well as those vanadyl−imidazole complexes previously published, reveals a trend in the contribution to the hyperfine coupling related to the orientation of the imidazole ring relative to the vanadyl unit; an imidazole parallel to the vanadium−oxygen double bond was found to have a contribution of 40 × 10-4 cm-1, while one perpendicular gave a contribution of 45 × 10-4 cm-1. A similar trend for imine values was also observed in the study of these complexes....

Vibrational characteristics of the double oxygen bridge in the NaIn(WO4)2 and NaSc(WO4)2 tungstates with wolframite structure

The normal coordinate analysis of the tungsten–oxygen core in NaIn(WO4)2 and NaSc(WO4)2 crystals was performed. The Urey–Bradley force field and potential energy distribution (PED) were applied in the internal and external phonon calculations for the W4O22Na2In2 molecular system. The dynamics of the asymmetric WO2W oxygen bridge as well as terminal WO bonds were analyzed and discussed. The vibrational characteristics of the oxygen double bridge bond, i.e. vibration energy, symmetry, force constants, PED, atomic displacements, direction of the transition dipole moments and mean square amplitudes were obtained and discussed. The theoretical considerations were based on the polarized IR and Raman spectra of the materials studied.

Protonic Conduction in P2O5-SiO2 Glasses Prepared by Sol-Gel Method

Protonic conduction in 10P2O5·90SiO2 and 20P2O5·80SiO2 (mol %) glasses prepared by sol-gel processing was investigated as a function of the content of molecular water adsorbed in the pores. The results show that the electrical conductivity of the glasses containing adsorbed molecular water varies exponentially with the reciprocal absolute temperature and increases with the increase of the content of the adsorbed molecular water. The double-bonded oxygen and the high affinity of phosphorus for oxygen make protons easily to release and transfer, which is favorable to the protonic conductivity.

Local Structure and Electronic State of Oxygens in Lithium Phosphate Glasses Calculated by Molecular Orbital Theory.

The validity of separating O1s photoelectron spectra of alkaline phosphate glasses into three peaks assigned to bridging, non-bridging and double-bonded oxygen atoms was discussed on the basis of the molecular orbital calculations by density functional method. Models used for the calculations were lithium metaphosphate chain clusters consisting of 2, 4 and 5 PO4 units. Two oxygen atoms around a Li+ ion, non-bridging oxygen and double-bonded oxygen, were structurally indistinguishable, and were considered to be classified into the same terminal atoms. The O1s orbital energies of these terminal oxygen atoms were consistent to each other within 0.4eV. The variation in orbital energies probably results from inhomogeneous broadening caused by the statistically distributed surroundings around PO4 units. From these results, it was concluded that in O1s photoelectron spectra of phosphate glasses, the separation of the lower binding energy side peak into two bands is not appropriate.

Stabilization of a germanium–oxygen double bond: a theoretical study

Both B3LYP and CCSD(T) computational results suggest that fluorine substitution can dramatically stabilize F2GeO, with respect to FGe–OF, both from a kinetic and from a thermodynamic viewpoint.

Raman Spectroscopic Determination of the Percent of Acetylation in Modified Wheat Starch

Raman spectroscopy was developed as an analytical method for rapid determination of the degree of acetylation in chemically modified wheat starches. The carbon oxygen double bond stretch Raman peak (∼1732 cm−1) of the modified wheat starches showed a linear relationship with acetylation over the range of 0 to 3.5% as determined from calibration plots with the standard titrimetric method currently used to measure acetylation of modified starches. The Raman spectroscopic method allows much faster determination of the degree of acetylation, is nondestructive, and has less problems with interference from impurities than currently used methods. Corresponding authors.

Kinetics of Acid-Catalyzed Hydrolysis of a Polyphosphate in Water

The zeroth-order reaction of the hydrolysis of sodium polyphosphate in water at pH = 0 can be explained assuming the formation of a pentacovalent terminal phosphorus intermediate. A terminal unit is activated for hydrolysis by protonation of the double-bond oxygen on that unit followed by a nucleophilic attack of water. Proton transfer from an OH group to a P−O−P bond breaks the bond, thereby shortening the phosphate polymer. A mathematical equation is developed to explain the reaction order of the hydrolysis.

Preparation of selective catalytic reduction catalysts via milling and thermal spreading

New catalyst preparation methods which avoid the formation of waste water are desirable for environmental reasons, especially in the case of catalysts produced in amounts as large as those in the DeNO x sector. Thermal spreading has recently been applied in the preparation of titania-supported tungsten and molybdenum monolayer catalysts. In this paper we compare catalysts which are prepared via ball milling of mixtures of the individual precursor oxides with subsequent thermal spreading to catalysts which are prepared by a conventional coprecipitation process. Titania (anatase) was milled in the presence of either tungsten trioxide or molybdenum trioxide and these mixtures were subsequently calcined in a stream of oxygen which contained water vapor. After calcination, no crystalline WO 3 or MoO 3 was detected by XRD or DRIFTS, indicating a good dispersion of the active oxides. The overtones of tungsten and molybdenum oxygen double bond vibrations, which are representative for the formation of surface polyoxo compounds, were detected with DRIFT spectroscopy for samples prepared either by coprecipitation or via ball milling. The intensity distribution of the hydroxyl groups for ball mill prepared samples was different from the distribution for coprecipitated samples. When the physical mixtures were milled for several hours, the anatase was transformed into rutile as shown by X-ray diffraction. Furthermore, a decrease in surface area and changes in the pore size distribution were observed in correlation with the milling.

Multiple Bonds Between Main Group Elements and Transition Metals. 151.1Trioxorhenium(VII) Alkoxide Complexes

The reaction of Me3SiOReO3 with trimethylsilyl ethers Me3SiOR (R = Me, CMe2CMe2OMe, CMe2CMe2OH, CMe2CMe2OSiMe3) yields the trioxorhenium(VII) alkoxide complexes [ReO3(OMe)(MeOH)]2 (1), ReO3(OCMe2CMe2OMe) (2), ReO3(OCMe2CMe2OH) (3), and the glycolate complex (Me3SiO)ReO2(OCMe2CMe2O) (4), respectively. The alkoxides 1−4 have fluxional structures at room temperature in solution on the 17O NMR time scale. The trigonal bipyramidal structure of 2, in the crystal, is static in solution only at −90 °C. The protic hydrogen of 3 can be abstracted by lithium 2,2,6,6-tetramethylpiperidinate to give the ionic complex Li[ReO3(OCMe2CMe2O)] (5). [ReO3(OMe)(MeOH)]2 (1) crystallizes from dichloromethane in the space group P1̄ with unit cell dimensions a = 6.276(3) Å, b = 6.720(3) Å, c = 8.005(4) Å, α = 109.39(3)°, β = 99.48(3)°, γ = 110.31(2)°, V = 238.3 Å3, and Z = 1; the structure was refined to R = 0.050 and Rw = 0.056. ReO3(OCMe2CMe2OMe) (2) crystallizes from toluene in the space group Pbca with unit cell dimensions a = 8.263(2) Å, b = 10.884(3) Å, c = 22.963(5) Å, V = 2065 Å3, and Z = 8; the structure was refined to R = 0.044 and Rw = 0.028. ReO3(OCMe2CMe2OH) (3) crystallizes from dichloromethane in the space group C2/c with unit cell dimensions a = 12.327(5) Å, b = 10.973(3) Å, c = 14.491(6) Å, β = 90.22(2)°, V = 1960 Å3, and Z = 8; the structure was refined to R = 0.047 and Rw = 0.030. (Me3SiO)ReO2(OCMe2CMe2O) (4) crystallizes from n-pentane in the space group P21/c with unit cell dimensions a = 12.042(8) Å, b = 10.782(2) Å, c = 12.485(9) Å, β = 117.44(3)°, V = 1439 Å3, and Z = 4; the structure was refined to R = 0.044 and Rw = 0.044. The edge-sharing bioctahedral complex 1 has bridging methoxy and terminal methanol ligands trans to rhenium−oxygen double bonds. The rhenium centers in compounds 2 and 3 are pentacoordinated and located in a distorted trigonal bipyramidal geometry. The alkoxy function of the alkoxy ligand −OCMe2CMe2OR (R = H, Me) is located in the equatorial plane, and the Lewis base (−OMe, −OH) is bonded trans to an oxygen atom in an axial coordination site. (Me3SiO)ReO2(OCMe2CMe2O) (4) has a similar geometry to 2 and 3 with a trimethylsiloxy ligand trans to an alkoxy function in an axial position.

Flavonoids as phospholipase A2 inhibitors: importance of their structure for selective inhibition of group II phospholipase A2.

The inhibitory effect of the plant flavonoid, rutin, on group I phospholipase A2 (PLA2-I) from porcine pancreas and Naja naja, and on group II phospholipase A2 (PLA2-II) from Vipera russelli and Crotalus atrox was investigated. Rutin efficiently inhibited PLA2-II from both Vipera russelli and Crotalus atrox but was only a weak inhibitor of PLA2-I from porcine pancreas and Naja naja. The lack of strong inhibition of pancreatic PLA2-I was not due to contaminating proteins in the enzyme preparation, since the same weak inhibition was obtained against pancreatic PLA2 purified to homogeneity as judged by two-dimensional gel electrophoresis. Rutin also efficiently inhibited human PLA2-II from synovial fluid but was only a weak inhibitor of human PLA2-I from pancreatic juice, suggesting that rutin is a selective PLA2-I from porcine pancreas. The results obtained indicate that the hydroxyl group in 5-position as well as the double bond and the double-bonded oxygen in the oxane ring are all important for the overall ability of flavonoids to inhibit PLA2 activity, and that the hydroxyl groups in 3'- and 4'- position are required for selective inhibition of PLA2-II.

Synthetic Methodology Allowing the Interconversion of Titanium–Oxygen Single Bonds and Double Bonds: The Self‐Assembly of Bridging and Terminal Oxotitanium(IV) into Oligomeric and Polymeric Linear Titanoxanes

AbstractThe controlled ionization of the linear [Cl–Ti–O–Ti–Cl] skeleton allowed the generation of the [Cl–Ti–O–Ti]+ dimer, which is nonsymmetrical as a consequence of extended Cl–Ti–O π interactions. The [TiO] unit thus formed is a building block for a variety of titanoxane structures. This chemistry has been investigated from a theoretical point of view by ab initio MO analysis of the [Cl–Ti–O–Ti–Cl] and [Cl–Ti–OTi]+ fragments. These calculations lead to the conclusion that single ionization generates the [TiO] unit, whereas double ionization does not affect the μ‐oxo bonding mode in [Ti–O–Ti]2+ or [S–Ti–O–Ti–S]2+ (where S is a pure σ‐donor ligand or solvent). This observation has been confirmed experimentally by ionizing the following model complexes: [(Cl)(acacen)‐Ti–O–Ti(acacen)(Cl)] (3) (acacen = N,N'‐ethylenebisacetylacetoneiminato dianion) and [(Cl)(salen)Ti–O–Ti(salen)‐(Cl)] (4) (salen = N,N'‐ethylenebissalicylideneiminato dianion), where the linear Cl–Ti–O–Ti–Cl unit is assured by the square‐planar bonding mode of the tetradentate Schiff base ligand. The double ionization of 3 with AgNO3 gave the conventional μ‐oxo derivative [(acacen)(η1‐ONO2)Ti–O–Ti(acacen)(η1‐ONO2)] (5). In contrast, the stepwise ionization of 3 and 4 with NaBPh4 in THF led to the nonsymmetrical [Cl–Ti–OTi]+ intermediates, which are the parent compounds for a variety of linear titanoxanes. The following species containing a TiO unit have been isolated from the NaBPh4‐assisted ionization of 3: [(acacen)TiO–BPh3] (6) and [(L)(acacen)TiO–Ti(acacen)–O–(acacen)Ti–OTi(acacen)(L)]2+2 BPh‐4 (L = THF, 7; L = none, 8). The same reaction carried out on 4 led to [(THF)‐(salen)TiO – Ti (salen) – O – (salen)Ti‐(THF)]2+2 BPh‐4 (9) and [(L)(salen)‐TiO–Ti(salen) – O – (salen)Ti–OTi‐(salen)(L)]2+ 2BPh‐4 (L = THF, 10; L = Py, 11; L = none, 12, polymeric form). A scheme is proposed to explain the formation of the species derived from the single ionization of 3 and 4, where the origin and the binding properties of the [TiO] unit play a major role.

Infrared-spectroscopic investigations of selective catalytic reduction catalysts poisoned with arsenic oxide

Titania-supported tungsten and molybdenum SCR catalysts were investigated before and after poisoning with arsenic(III) oxide. Diffuse reflectance and transmission infrared spectroscopy, including the adsorption of carbon monoxide and ammonia as probe molecules, were applied. The surface of the unpoisoned catalysts is characterized by hydroxyl groups of the support and by surface polytungstate and polymolybdate species carrying terminal metal oxygen double bonds. Carbon monoxide adsorbs on coordinatively unsaturated (cus) metal cations, representing Lewis acid sites, and via H-bonding on hydroxyl groups, representing Brønsted acid sites. From the carbon monoxide adsorption data it is concluded, that the cus cations on tungsten containing samples are stronger Lewis acid sites than those on molybdenum containing samples. Ammonia is adsorbed on Lewis acid sites on both catalysts. Poisoning of the samples by arsenic(III) oxide leads to replacement of the hydroxyl groups by new species that are assigned to arsenic-hydroxyls of a well distributed surface arsenate species. Interaction of the arsenate with the polyoxostructures is shown by the perturbation of the metal-oxygen stretching band of the active phase after poisoning. Important with regard to catalysis may be the fact that neither carbon monoxide nor ammonia can be adsorbed on Lewis surface sites on catalysts poisoned with sufficient amounts of arsenic(III) oxide.

Studies on peroxomolybdates. XIX. Crystal structure of potassium heptaoxotetraperoxotrimolybdate(VI)-water( [formula omitted]) K 4[Mo 3O 7(O 2) 4]·2H 2O

The crystal structure of potassium heptaoxotetraperoxotrimolybdate(VI)-water( 1 2 ), K 4[Mo 3O 7(O 2) 4]·2H 2O, has been determined from single-crystal X-ray diffraction data. The yellow compound crystallizes in the triclinic space group P 1 with a = 8.470(1), b = 12.297(3), c = 8.407(2) A ̊ , α = 103.56(2)°, β = 104.32(1)°, γ = 103.40(1)°, V = 784.8(3) A ̊ 3 and Z = 2. Full-matrix least-squares refinement of 218 structural parameters gave R = 0.026 for 4415 observed [ I > 3 σ( I)], independent reflections. In the [Mo 3O 7(O 2) 4] 4− anion two molybdenum atoms are seven-coordinated and one molybdenum atom is four-coordinated. The anion can be described as being composed of two edge-sharing pentagonal bipyramids sharing one common corner with a tetrahedron. In the pentagonal bipyramids the molybdenum atoms are displaced 0.314–0.317 Å from the equatorial plane towards the double-bonded apical oxygen atom. The three molybdenum atoms are situated at the corners of an isosceles triangle with the two seven-coordinated molybdenum atoms (Mo pbp) at the base. Selected bond distances: MoO peroxo 1.933(3)-1.991(3) Å, Mo pbpO apical 1.683(3)–1.695(3) Å, Mo pbpO apical 2.301(2)–2.334(2) Å and (OO) peroxo 1.460(5)–1.487(4) Å. Mo ⋯ Mo is 3.3612(4), 3.7037(5) and 3.7306(7) Å.

Preparation of bis(phosphine)bis(selenocarboxylato)-nickel(II), -palladium(II) and -platinum(II) complexes and their crystal structure analysis

A series of bis(triorganophosphine)bis(selenocarboxylato)-nickel(II)3, -palladium(II)4 and -platinum(II)5 complexes have been synthesised from the reaction of sodium selenocarboxylates 1 or O-silyl selenocarboxylates 2 with the corresponding bis(phosphine)metal dichloride in good to high yields and have been characterized by 1H, 13C, 31P and 77Se NMR spectroscopy and elemental analysis. Additionally [M(4-MeC6H4COSe)2(PEt3)2](M = Ni 3d, Pd 4d or Pt 5b) have been crystallographically characterized and reveal four-co-ordinate planar structures with each of the two selenocarboxylate and phosphine ligands lying trans. The carbon–oxygen bond lengths [1.209(6), 1.203(8) and 1.212(6)A] of the selenocarboxylate ligand of 3d, 4d and 5d show values typical of a carbon–oxygen double bond; co-ordination of the carbonyl oxygen to the metal is not observed.

Synthesis of Rubidium and Cesium Tellurocarboxylates and an X-Ray Structural Analysis of Heavy Alkali Metal Monochalcogenocarboxylates

Abstract A series of rubidium and cesium tellurocarboxylates (2 and 3) were synthesized from the reaction of O-trimethylsilyl tellurocarboxylates (1) with rubidium and cesium fluorides in moderate isolated yields and characterized by 1H, 13C, and 125Te NMR spectroscopy and X-ray diffraction. The carbon–oxygen distance [1.235(6) Å] of the tellurocarboxyl group of crystalline cesium 2-methoxybenzenecarbotelluroate (3f) showed a typical value of the carbon–oxygen double bond. The crystal packing of 3f shows the possibility of an interaction between the cesium cation and the aromatic ring carbon. The thio- and selenocarboxyl groups of the corresponding sulfur and selenium isologues (4 and 5) also indicate a double bond [1.231(4) and 1.226(5) Å] between the carbon and oxygen, respectively. The salts (2 and 3) readily react with iodomethane to afford the corresponding Te-methyl tellurocarboxylates in good yields. The reaction between 3 and tetramethylammonium chloride was found to give a novel quaternary ammonium salt (8) of tellurocarboxylic acid, where the dihedral angle between benzene ring and the tellurocarboxyl group of 8 is ca. 90°. Crystallographic data for 3f, 4, 5, and 8 are as follows. 3f: P21/n, a = 7.182(2), b = 12.161(5), c = 12.151(3) Å, β = 92.57(2)°, V = 1060.2(6) Å3, dcalcd = 2.479 g cm−3, Z = 4, R = 0.035, Rw = 0.043. 4: Pbca, a = 8.995(2), b = 29.936(2), c = 7.291(1) Å, V = 1963.3(5) Å3, dcalcd = 2.030 g cm−3, Z = 8, R = 0.024, Rw = 0.021. 5: Pbca, a = 9.290(1), b = 30.207(2), c = 7.193(2) Å, V = 2018.5(3) Å3, dcalcd = 2.284 g cm−3, Z = 8, R = 0.029, Rw = 0.020. 8: P212121, a = 11.844(2), b = 14.014(2), c = 8.650(1) Å, V = 1435.8(3) Å3, dcalcd = 1.558 g cm−3, Z = 4, R = 0.044, Rw = 0.047.

Studies on peroxomolybdates XVIII. Crystal structure of ammonium μ-fluoro- μ-oxo-bis[oxodiperoxomolybdate(VI)]- water(2/1), [formula omitted], a dibridged peroxodimolybdate

The crystal structure of ammonium μ- fluoro-μ- oxo-bis[oxodiperoxomolybdate(VI)]-water (2 1) , (NH 4) 3[FO{MoO(O 2) 2} 2]· 1 4 H 2O , has been determined from single-crystal X-ray diffraction data. The yellow compound crystallizes as multiple-twins in the monoclinic space group P2 1/ c with a = 13.803(3) A ̊ , b = 11.230(2) A ̊ , c = 15.975(3) A ̊ , β = 109.46(2)° and Z = 8. Full-matrix least-squares refinement of 316 structural parameters gave R = 0.057 for 3265 observed [ I > 3 σ( I)], independent reflections. The [FO{MoO(O 2) 2} 2] 3− anions, of which there are two crystallographically different ones in the asymmetric unit, have approximately C 2v symmetry and are composed of two edge-sharing pentagonal bipyramids, the molybdenum atoms thus being seven-coordinated. The molybdenum atoms are displaced 0.312–0.365 Å from the equatorial planes towards the respective double-bonded apical oxygen atom. Bond distances are as follows: MoO peroxo 1.884(10)–1.975(8) Å, Mo = O apical 1.670(8)–1.682(8) Å, MoF bridge 2.246(6)–2.313(6) Å, MoO bridge 1.925(7)–1.941(7) Å and (OO) peroxo 1.436(15)–1.465(12) Å. Mo ··· Mo is 3.369(1)–3.379(1) Å, MoOMo 120.5(4)–122.6(4)° and MoFMo 94.0(2)–95.5(2)°. The powder photograph of the title compound was recorded at room temperature and was indexed.

Organic inclusions in salt. Part I: Solid and liquid organic matter, carbon dioxide and nitrogen species in fluid inclusions from the Bresse basin (France)

Organic inclusions from the Etrez and Cormoz areas of the Paleogene Bresse salt basin (France) have been studied. Different organic fractions are trapped with brine solutions in fluid inclusions in halite. Isolated inclusions from both areas are brine-bearing, and organic matter is sometimes associated with daughter mineral phases (carbonate, sulfate, clay). Structured and unstructured solid organic matter is observed both in the Etrez area (central basin) and in the Cormoz area (Northern ridge), while liquid organic droplets are only observed in fluid inclusions from the Cormoz area. FTIR microspectroscopic measurements show a low aliphatic contribution, and the presence of aromatic and oxygen double bonds for the solid organic matter. Low to high aliphatic contents (C5 and C7+, deduced from CH 2 CH 3 ratio measurements), low to high CC and CO contributions, and the presence of characteristic CN functions of amino-acids are detected in liquid droplets by FTIR spectroscopy. Carbon dioxide, originating from the thermal degradation of solid organic matter, is generally detected. Organic two-phase inclusions (brine + liquid organic matter) in planes are located in clear halite crystals from the Cormoz area. High aliphatic contributions, and variable aromatic and oxygen contents are observed. Ammonium ions (NH 4 +) are detected in the brine solution, and no carbon dioxide contribution is recorded. Organic matter trapped in the halite of the Bresse basin is immature to early mature. In the deeper part of the basin (Etrez, 800–1000 m), the organic matter in the inclusions is slightly thermally degraded, with little or no generation of liquid organic compounds. This agrees with the data on organic matter previously published from this area. In the Northern ridge (Cormoz, 500–800 m), liquid heteroatomic compounds (C, H, O, N) were produced, migrated through the salt and were trapped without gas phases. This implies a slightly lower temperature in the deeper part (Etrez) of the Bresse basin. Differences in thermal gradients between the Northern ridge, and the deeper part of the Bresse basin, must be invoked to explain differences in organic matter maturation. The analysis of organic inclusions is a contribution to understanding the thermal and biochemical history of the Bresse basin by the in situ observation of organic evolution products which are preserved by entrapment in salt.