Fluoro-benzene Rings Research Articles

N-{3-[2-(4-Fluorophenoxy)ethyl]-2,4-dioxo-1,3-diazaspiro[4.5]decan-7-yl}-4-methoxybenzenesulfonamide

In the title compound, C23H26FN3O6S, the two terminal aromatic rings form a dihedral angle of 49.26 (12)°. The cyclo­hexane ring adopts a chair conformation and the five-membered ring is essentially planar, with a maximum deviation from planarity of 0.0456 (19) Å. The dihedral angles between the five-membered ring and the meth­oxy­benzene and fluoro­benzene rings are 33.56 (11) and 81.94 (12)°, respectively. The crystal structure displays N—H⋯O hydrogen bonds as well as weak inter­molecular C—H⋯O inter­actions.

(2E)-3-(3-Bromo-4-methoxyphenyl)-1-(4,4′′-difluoro-5′-methoxy-1,1′:3′,1′′-terphenyl-4′-yl)prop-2-en-1-one

In the title compound, C29H21BrF2O3, the dihedral angles between the central anisole ring and the pendant fluoro­benzene rings are 48.86 (19) and 31.89 (18)°. The dihedral angle between the anisole ring and the 1-bromo-2-meth­oxy­benzene ring linked via the enone bridge is 82.95 (17)°. In the crystal, C—H⋯O hydrogen bonds link the mol­ecules into C(11) chains propagating along [010].

2-(4-Fluorophenyl)-3-isopropylsulfinyl-5,6-methylenedioxy-1-benzofuran

In the title compound, C18H15FO4S, the fluoro­benzene ring makes a dihedral angle of 4.3 (1)° with the mean plane of the benzofuran fragment. In the crystal, mol­ecules are linked by weak inter­molecular C—H⋯O hydrogen bonds. The O atom of the sulfinyl group is disordered over two orientations, with site-occupancy factors of 0.940 (3) and 0.060 (3).

3-({(E)-2-[(4-Fluorophenyl)carbamothioyl]hydrazinylidene}methyl)-4-hydroxybenzyl]methyltriphenylphosphonium chloride

The cation in the title salt, C33H28FN3OPS+·Cl−, is highly twisted with the phospho­nium group occupying a position almost normal to the central hydroxyl­benzene ring [P—C—C—C tosrsion angle = −100.9 (3)°], and with the hydrazone substituent twisted out of the plane [C—C—C—N torsion angle = 13.1 (4)°]. The fluoro­benzene ring is twisted out of the plane of the adjacent thio­urea residue, forming a dihedral angle of 51.69 (10)°. The configuration about the C=N bond [1.281 (4) Å] is E, the O—H and N—H hydrogen atoms are syn, and in the thio­urea residue, the N—H hydrogen atoms are anti, allowing for the formation of an intra­molecular N—H⋯N hydrogen bond. In the crystal, dimeric aggregates mediated by N—H⋯S bonds are formed, which are linked to the Cl− anions by O—H⋯Cl hydrogen bonds. The four-component aggregates are linked into a three-dimensional structure by C—H⋯Cl inter­actions.

N,N,N′,N′-Tetraethyl-N′′-(2-fluorobenzoyl)phosphoric triamide

In the title compound, C15H25FN3O2P, the phosphoryl group is in an anti and syn orientation to the C=O and N—H groups, respectively. The P atom is in a distorted tetra­hedral environment. One of the ethyl groups is disordered over two sets of sites with refined occupancies of 0.755 (6) and 0.245 (6). In addition, the F atom was refined as disordered with occupancies fixed at 0.9 and 0.1. This disorder corresponds to a rotation of approximately 180° of the fluoro­benzene ring about its connecting C—C bond. In the crystal, pairs of inter­molecular N—H⋯O(=P) hydrogen bonds form centrosymmetric dimers.

(2E)-3-(3-Bromo-4-methoxyphenyl)-1-(4-fluorophenyl)prop-2-en-1-one

In the title compound, C16H12BrFO2, the dihedral angle between the aromatic rings is 23.75 (12)° and the dihedral angle between the prop-2-en-1-one fragment and the fluorobenzene ring is 20.9 (2)°. In the crystal, only van der Waals interactions occur.

1,1′-Bis(4-fluorophenyl)-3,3′-diisobutyl-4,4′-diphenoxy-1H,1′H-4,4′-bipyrazole-5,5′(4H,4′H)-dione

In the title compound, C38H36F2N4O4, the pyrazole rings form dihedral angles of 50.02 (4) and 18.05 (4)° with their attached fluorobenzene rings, and make dihedral angles of 76.08 (4) and 73.54 (5)° with the aromatic ring of the attached phen­oxy group. In the crystal, the molecules are connected by weak C—H⋯π inter­actions.

5-Ethyl-2-(4-fluorophenyl)-4-phenoxy-1H-pyrazol-3(2H)-one

In the title compound, C17H15FN2O2, the essentially planar pyrazole ring [maximum deviation = 0.026 (1) Å] makes dihedral angles of 72.06 (7) and 33.05 (7)°, with the phenyl and fluoro­benzene rings, respectively. The dihedral angle between the two six-membered rings is 87.88 (7)°. In the crystal, inter­molecular N—H⋯O and C—H⋯F hydrogen bonds link the mol­ecules into layers lying parallel to the bc plane.

2-Amino-4-(2-fluorophenyl)-5,6-dihydrobenzo[h]quinoline-3-carbonitrile

In the title compound, C20H14FN3, the F atom of the fluoro-substituted benzene ring in the 4-position of the 5,6-dihydro­benzo[h]quinoline system is disordered over two positions (0.80 and 0.20 occupancy). The dihedral angle between the pyridine and fluorobenzene rings is 73.2 (2) Å. The crystal structure is established by inter­molecular N—H⋯N hydrogen bonds, forming a three-dimensional network.

N-[3-Chloro-4-(3-fluoro-benz-yloxy)phen-yl]-6-iodo-quinazolin-4-amine.

In the title mol­ecule, C21H14ClFIN3O, the bicyclic ring system has a twisted conformation; the two fused rings form a dihedral angle of 4.5 (1)°. The dihedral angles between the fused ring system and the benzene rings are 27.3 (6) and 5.3 (5)° while the dihedral angle between the benzene rings is 22.0 (5)°. In the crystal structure, weak inter­molecular N—H⋯N hydrogen bonds link the mol­ecules into chains propagating in [100]. A short inter­molecular distance of 3.806 (3) Å between the centroids of the fluorobenzene and iodobenzene rings suggests the existence of π–π stacking inter­actions.

N-[Bis(4-fluorophenyl)methylene]aniline

The title compound, C19H13F2N, was synthesized by an addition reaction of bis­(4-fluoro­phen­yl)methanone with aniline. The dihedral angles formed by the fluoro­benzene rings with the aniline ring are 81.04 (5) and 64.15 (5)°. In the crystal packing, inter­molecular C—H⋯F hydrogen bonds link mol­ecules into zigzag chains parallel to the c axis.

N-(2-Fluorophenyl)cinnamamide

The title compound, C15H12FNO, was prepared by the reaction of cinnamoyl chloride with 4-fluoro­aniline and crystallizes with two mol­ecules A and B in the asymmetric unit. The two unique mol­ecules are closely similar and overlay with an r.m.s. deviation of 0.0819 Å. The fluoro­benzene and phenyl rings are inclined to one another at 73.89 (7) and 79.46 (7)°, respectively, in mol­ecules A and B. The amide C—N—C(O)—C portions of the mol­ecules are planar (r.m.s. deviations = 0.035 and 0.028 Å) and are inclined at 45.51 (9) and 47.71 (9), respectively, to the fluoro­benzene rings in mol­ecules A and B. The 2-fluoro­acetamide units and the benzene rings each adopt E configurations with respect to the C=C bonds. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds augmented by weak C—H⋯π inter­actions link mol­ecules into rows in a head-to-tail fashion along a. Additional weak C—H⋯O contacts further stabilize the packing, forming a three-dimensional network stacked down a.

2-Fluoro-N-o-tolylbenzamide

In the title compound, C14H12FNO, the ortho-F atom and corresponding H atom on the fluoro­benzene ring are disordered over two positions with occupancies of 0.856 (4) and 0.144 (4). The amide unit is planar with a maximum deviation of 0.0057 (16) Å and the amide plane makes dihedral angles of 38.27 (11)° with the fluoro­benzene ring plane and 37.53 (10)° with the tolyl ring. The two benzene rings are inclined at an angle of 4.17 (15)°. In the crystal structure, chains form along b through N—H⋯O hydrogen bonds augmented by C—H⋯π inter­actions. Additional inter­molecular C—H⋯O and C—H⋯F hydrogen bonds further stabilize the structure, forming layers in the ac plane.

2,2′-Bis(4-fluoroanilino)-3,3′-(3,6-dioxaoctane-1,8-diyl)diquinazolin-4(3H)-one

In the centrosymmetric title compound, C34H30F2N6O4, the dihedral angle between the quinazolinone and fluorobenzene ring planes are 71.00 (2) and 74.94 (2)° and an intra­molecular N—H⋯O interaction stabilizes the conformation. In the crystal, C—H⋯F and C—H⋯O links help to establish the packing.

N-Cyclohexyl-2-fluorobenzamide

In the title compound, C13H16FNO, the fluoro­benzene ring plane and the plane through the amide unit are inclined at a dihedral angle of 29.92 (7)°. The cyclo­hexane ring adopts a chair conformation. In the crystal structure, N—H⋯O hydrogen bonds, augmented by weak C—H⋯O inter­actions, link the mol­ecules into transverse chains along a. These chains are linked into zigzag columns down a by C—H⋯F hydrogen bonds and C—H⋯π inter­actions.

1-[2-(4-Fluorobenzyloxy)-2-phenylethyl]-1H-benzimidazole

The asymmetric unit of the title compound, C22H19FN2O, contains two independent mol­ecules. The planar benzimidazole ring systems are oriented with respect to the phen­yl/fluoro­benzene rings at dihedral angles of 31.10 (4)/45.17 (5) and 45.52 (5)/68.63 (5)°, respectively, for the two mol­ecules. In the crystal structure, inter­molecular C—H⋯N and inter­molecular C—H⋯N and C—H⋯F hydrogen bonds link the mol­ecules into a three-dimensional network. There are C—H⋯π contacts between the benzimidazole and fluoro­benzene rings and a π–π contact between the benzimidazole and phenyl ring systems [centroid–centroid distance = 4.575 (1) Å].

A practical route for synthesizing a PET ligand containing [ 18F]fluorobenzene using reaction of diphenyliodonium salt with [ 18F]F −

The aim of this study was to develop a practical route for preparing a fluorine-18 ([ 18F]) labelled ligand ([ 18F] 1) containing [ 18F]fluorobenzene ring by employing the reaction of diphenyliodonium salt with [ 18F]F −. Diphenyliodonium tosylate ( 2) was synthesized from tributylphenylstannyl compound ( 6) with [hydroxy(tosyloxy)iodo]benzene ( 7). Using this method, [ 18F]DAA1106 ([ 18F] 3a), a positron emission tomography ligand for imaging peripheral-type benzodiazepine receptor, was prepared.

The Fluorobenzene−Argon S1 Excited-State Intermolecular Potential Energy Surface

We evaluate the first excited-state (S1) intermolecular potential energy surface for the fluorobenzene-Ar van der Waals complex using the coupled cluster method and the augmented correlation-consistent polarized valence double-zeta basis set extended with a set of 3s3p2d1f1g midbond functions. To calculate the S(1) interaction energies, we use ground-state interaction energies evaluated with the same basis set and the coupled cluster singles and doubles (CCSD) including connected triple excitations [CCSD(T)] model and interaction and excitation energies evaluated at the CCSD level. The surface minima are characterized by the Ar atom located above and below the fluorobenzene ring at a distance of 3.5060 A with respect to the fluorobenzene center of mass and at an angle of 5.89 degrees with respect to the axis perpendicular to the fluorobenzene plane. The corresponding interaction energy is -425.226 cm(-1). The surface is used in the evaluation of the intermolecular level structure of the complex, and the results are compared to the experimental data available and to those found in previous theoretical papers on ground-state potentials for similar complexes.

1-Acetyl-3-(4-chlorophenyl)-5-(4-fluoro-3-phenoxyphenyl)-1H-pyrazole

In the title compound, C23H18ClFN2O2, the dihedral angles between the pyrazole ring and the attached chlorophenyl ring, the planar acetyl group and the fluorobenzene ring of the phenoxyphenyl unit are 3.3 (1), 5.2 (2) and 74.9 (1)°, respectively. The crystal structure is stabilized by intermolecular C—H...O hydrogen bonds and a short Cl...F contact.

The microwave spectrum, ab initio analysis, and structure of the fluorobenzene–hydrogen chloride complex

The fluorobenzene–hydrogen chloride π-hydrogen-bonded complex has been studied by high resolution microwave spectroscopy and ab initio calculations. Rotational spectra of the C6H5F–H35Cl, C6H5F–H37Cl, and C6D5F–H35Cl isotopomers were assigned using pulsed molecular beam techniques in a Fourier-transform microwave spectrometer. The spectra are consistent with a structure of the complex in which the HCl is above the fluorobenzene ring near the ring center, similar to the benzene–HCl prototype dimer. An analysis of the inertial data and the chlorine quadrupole coupling tensor results in two mathematically possible locations for the HCl subunit with respect to the fluorobenzene arising from sign ambiguities in interpreting the spectral constants. One structure has the HCl nearly perpendicular to the aromatic ring; the other has the HCl pointing toward the fluorine end of the ring. Spectral intensities for the μa and μb transitions favor the former configuration. Ab initio calculations (MP2/6-311++G(2df,2pd)+BSSE corrections) indicate that the position of the HCl is driven by electrostatic interactions with the π electrons of the benzene ring. HCl is shifted by 0.16 Å from the center of the ring toward the para-C atom, where the π density is significantly higher. In the equilibrium form, HCl is tilted by δ=14° from perpendicular to the ring with the hydrogen end toward the para-C atom. The H atom can perform an internal rotation or at least a half-circular libration (barriers smaller than 100 cm−1). An average δ value of 0.7° is estimated in reasonable agreement with the derived vibrationally averaged value of 3.8°. The complex binding energy ΔE calculated at the CCSD(T)/6-311++G(2df,2pd)+CP(BSSE) level of theory is 2.8 kcal/mol, suggesting a lower ΔE value for benzene–HCl than previously reported. Fluorobenzene–HCl possesses some charge transfer character; however, just 5.5 melectron are transferred from the benzene ring to HCl. In view of this, π–H bonding in fluorobenzene–HCl is predominantly electrostatic rather than covalent in character contrary to claims made in connection with benzene–HCl.