Manganese Tricarbonyl Complexes Research Articles

Regioselective Protonation of the η4-Anthracene Ligand in [Mn(η4-C14H10)(CO)3]-To Give an η5-Anthracenyl Complex [Mn(η5-C14H11)(CO)3] That Undergoes a Low-Energy 1,4-Hydride Exchange Reaction

Protonation of the terminal (η4-anthracene) manganese tricarbonyl anion [Mn(η4-C14H10)(CO)3]- gives the terminal (η5-anthracenyl) manganese tricarbonyl complex [Mn(η5-C14H11)(CO)3]. Single-crystal X-ray diffraction analysis confirms that the proton adds to the hydrocarbon ring, and labeling studies indicate that protonation is regiospecific and occurs at the endo site. Magnetization transfer experiments establish rapid spin population transfer from the exo site to the para ring position. This is proposed to involve an intermediate metal hydride, and dynamic NMR studies have been used to determine that the free energy barrier to this exchange is ca. 14.5 kcal/mol at and below ambient temperatures. This is interpreted in terms of a modification of the mechanism of Lamanna and Brookhart for the isomerization within 6-exo-1H-[Mn(η5-C6HD5)(CO)3].

Haptotropic shifts in organometallic complexes with η 5-coordinated π ligands

The electronic structure and bonding of a series of tricarbonylmanganese complexes, [(η n -X)Mn(CO) 3] m , were studied by means of ab initio calculations using the B3LYP hybrid functional with a LANL2DZ basis set. The following complexes with hydrocarbon ligands were addressed ( n=5, m=0): X=cyclopentadienyl (Cp=C 5H 5 −), indenyl (Ind=C 9H 7 −), fluorenyl (flu=C 13H 9 −), cyclopenta[ def]phenanthrenyl (cpp=C 15H 9 −), 8-hydro- as-indacene ( as-ind=C 12H 9 −) and 5-hydro- s-indacene ( s-ind=C 12H 9 −). Two complexes with heterocyclic ligands, X=pyrrolyl (pyr=NC 4H 4 −, n=5, m=0) and X=thiophene (tp=SC 4H 4, n=5, m=1+) were also studied. For all those species, in which X is a η 5-coordinated π ligand, the bonding was analysed, and the optimised structures were compared with the experimentally determined X-ray structures, available from the literature. The results show a weakening of the (η 5-X)Mn bond with the increasing of the ligands π system extension. The η 3 species resulting from a two electrons reduction of the previous complexes were studied, their structures optimised, and a comparison between the different coordination geometries of η 3-X is provided. Thus, for the fluorenyl and cyclopenta[ def]phenanthrenyl complexes, an exocyclic allylic coordination was found for the reduced species ( n=3, m=2−). For the indenyl and indacene reduced complexes two possible coordination geometries were studied, the exocyclic and the folded η 3-X, the latter being found the more stable for all these species (X=Ind, as-ind, s-ind; n=3, m=2−). The heterocyclic ligands were shown to adopt a σ rather than a η 3 coordination geometry, in the corresponding reduced complexes ( m=2− for pyr and m=1− for tp).

Addition of Stabilized Carbanions to Cationic (η6-Arene)tricarbonylmanganese Complexes: Syntheses of Homo (Mn–Mn) and Hetero (Mn–Cr) Dinuclear Complexes

Addition of Stabilized Carbanions to Cationic (η6-Arene)tricarbonylmanganese Complexes: Syntheses of Homo (Mn–Mn) and Hetero (Mn–Cr) Dinuclear Complexes

Addition of Stabilized Carbanions to Cationic (η6-Arene)tricarbonylmanganese Complexes: Syntheses of Homo (Mn–Mn) and Hetero (Mn–Cr) Dinuclear Complexes

The reaction of secondary α-cyano or α-sulfonyl carbanions with cationic (η6-arene)tricarbonylmanganese complexes affords neutral mono- and dinuclear tricarbonyl(η5-cyclohexadienyl)manganese complexes. The X-ray analyses of three (η5-cyclohexadienyl)Mn complexes (two mononuclear and one dinuclear) obtained by addition of α-cyano carbanion to cationic (η6-arene)manganese complexes are reported. The addition of benzylic carbanions of (η6-arene)tricarbonylchromium complexes to cationic (η6-arene)manganese complexes gives rise to the formation of the corresponding heterodinuclear [(η5-cyclohexadienyl)manganese–(η6-arene)chromium] complexes.

Cationic manganese(I) tricarbonyl complexes with group 15 and 16 donor ligands: synthesis, multinuclear NMR spectroscopy and crystal structures

The compound [MnBr(CO)5] reacted with [10]aneS3 (1,4,7-trithiacyclodecane) in dmf solution to yield fac-[Mn(CO)3([10]aneS3)]Br. The compounds fac-[Mn(CO)3(L)]CF3SO3 (L = MeS(CH2)2S(CH2)2SMe, MeSe(CH2)3Se(CH2)3SeMe, MeC(CH2SMe)3, MeC(CH2SeMe)3, MeC(CH2TeMe)3, MeC(CH2TePh)3, MeC(CH2PPh2)3 MeC(CH2AsMe2)3 or Ph2P(CH2)2PPh(CH2)2PPh2) were readily obtained by treatment of fac-[Mn(CO)3(Me2CO)3]CF3SO3 with L at room temperature in Me2CO solution. Similar reactions using three molar equivalents of PPh2H, PCy2H or PPhH2 (L) yielded fac-[Mn(CO)3(L)3]CF3SO3 as pale yellow solids. The compounds have been characterised by analysis, IR and multinuclear NMR spectroscopy (1H, 13C-{1H}, 31P-{1H}, 55Mn, 77Se-{1H} and 125Te-{1H}), mass spectrometry and by single crystal X-ray diffraction studies on seven examples. The compounds all adopt a distorted octahedral arrangement with C3v local symmetry at MnI, and three mutually fac carbonyl ligands. The δ(55Mn) linewidths are very dependent upon subtle changes in the electric field gradient and for some of the phosphine complexes quartet coupling to 31P is clearly resolved giving 1JMnPca. 200 Hz. The spectroscopic data are discussed in terms of the relative bonding properties of the Group 15 or 16 donor ligands within the manganese(I) cation.

(η 6-Arene)tricarbonylchromium and (η 5-cyclohexadienyl) tricarbonylmanganese complexes: indirect nucleophilic substitutions

Treatment of X-substituted (η 6-arene)tricarbonylchromium complexes with a nucleophile and a proton source afforded new arenetricarbonylchromium complexes via chromium hydride intermediates and elimination of HX ( cine and tele nucleophilic aromatic substitutions). Treatment of (η 5-X-substituted-cyclohexadienyl)tricarbonyl manganese complexes with hydride and a proton source gave η 5-cyclohexadienyl complexes resulting from a cleavage of the C–X bond: the η 3-X-substituted cyclohexenyl intermediates underwent elimination of an agostic hydrogen and the X group.

Chelated alkyl halide manganese complexes ( η5: η1-C 5H 4CH 2CH 2X)Mn(CO) 2 from photolysis of ( η5-C 5H 4CH 2CH 2X)Mn(CO) 3

Manganese tricarbonyl complexes ( η 5-C 5H 4CH 2CH 2Br)Mn(CO) 3 ( 3) and ( η 5-C 5H 4CH 2CH 2I)Mn(CO) 3 ( 4), with an alkyl halide side chain attached to the cyclopentadienyl ligand, were synthesized as possible precursors to chelated alkyl halide manganese complexes. Photolysis of 3 or 4 in toluene, hexane or acetone-d 6 resulted in CO dissociation and intramolecular coordination of the alkyl halide to manganese to produce ( η 5: η 1-C 5H 4CH 2CH 2Br)Mn(CO) 2 ( 5) and ( η 5: η 1-C 5H 4CH 2CH 2I)Mn(CO) 2 ( 6). Low temperature NMR and IR spectroscopy established the structures of 5 and 6. Photolysis of 3 in a glass matrix at 91 K demonstrated CO release from manganese. Low temperature NMR spectroscopy established that the coordinated alkyl halide complexes are stable to approximately −20°C.

Reactivity of Cyclomanganated 2-Phenylpyridine Derivatives toward Organolithium Reagents. Synthesis of Novel Chelated Tricarbonyl(η3-benzyl)manganese(I) Complexes

Ortho-manganated 2-arylpyridine and -quinoline derivatives were treated with aryllithium reagents and subsequently with alkyl triflates to yield air-stable chelated (η3-benzyl)tricarbonylmanganese complexes. Addition of PhLi to the cyclomanganated complex of 2-phenylpyridine [NC5H4−C6H4−Mn(CO)4], 1, followed by methylation with MeOTf afforded a red air-stable chelated η3-benzyl, tricarbonyl{2-[(1,2-η2),κCα-2-(phenylmethoxymethylene)phenyl]pyridine- κN}manganese(I), complex 4a. The molecular structure of 4a was established by single-crystal X-ray diffraction analysis. The study of this structure indicates a helical shape in which the manganese center adopts an octahedral configuration. Spectroscopic analysis indicates that the addition of the aryllithium reagent to 1 generates a new temperature- and air-sensitive benzoylmanganate species. The latter and other anionic acylmanganese species generated from different substrates readily decompose above a temperature of 0 °C to yield ketones and a formal [Mn(CO)...

ChemInform Abstract: Chiral Auxiliary Promoted Asymmetric Nucleophile Additions to Arene‐ Manganese Tricarbonyl Complexes.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Hydrodemethoxylation, Hydrodechloration, Hydrodesulfurization, and Hydrodeamination of Neutral (η5-X-substituted-cyclohexadienyl)tricarbonylmanganese Complexes (X = OMe, Cl, SPh, NEt2) upon Treatment with Hydride and Then Acid: cine and tele Nucleophilic Substitutions

Treatment of (η5-X-substituted-cyclohexadienyl)tricarbonylmanganese complexes (X = alkoxy, halogeno, dimethylamino and thio) with hydrides and a proton source gave η5-cyclohexadienyl complexes resulting from a cleavage of the C−O, C−Cl, C−N and C−S bonds: The η3-substituted cyclohexenyl intermediates underwent elimination of an agostic hydrogen and the alkoxy, halogeno, amino, or thio group.

Investigation of the Electronic and Geometric Effects of Trifluoromethyl Substituents on Tris(pyrazolyl)borate Ligands Using Manganese(I) and Copper(I) Complexes

Manganese tricarbonyl complexes of fluorinated tris(pyrazolyl)borate ligands [HB(3,5-(CF3)2Pz)3]- and [HB(3-(CF3)Pz)3]- (where Pz = pyrazolyl) were synthesized by treating BrMn(CO)5 with [HB(3,5-(CF3)2Pz)3]Ag(THF) or [HB(3-(CF3)Pz)3]Na(THF). The reaction of [HB(3-(CF3)Pz)3]Na(THF) with copper(I) trifluoromethanesulfonate under CO afforded [HB(3-(CF3)Pz)3]CuCO. Compounds [HB(3,5-(CF3)2Pz)3]Mn(CO)3 (5), [HB(3-(CF3)Pz)3]Mn(CO)3 (6), and [HB(3-(CF3)Pz)3]CuCO (7) were characterized by 1H NMR, 19F NMR, and IR spectroscopy and by X-ray crystallography. They have relatively high C−O stretching frequencies. However, the νCO values are much lower than that in free CO and the relative lowering is higher for manganese adducts. The CF3 substitution on the 5-position has a significant effect on the metal center. This is readily apparent from the infrared spectroscopic data. Theoretical calculations of the geometries of [tris(pyrazolyl)borato]manganese(I) and -copper(I) carbonyls are in excellent agreement with the expe...

55Mn and 187Re NQR spectral studies of modulation effects of mutual motions of electrons and atomic nuclei in cyclopentadienyl tricarbonyl manganese and rhenium complexes

The 55Mn and 187Re NQR spectral parameters for cyclopentadienyl tricarbonyl complexes of these metals at 77 K are presented. An analytical dependence between e 2 Qq zz and η has been shown to exist. Such dependence may be associated with slow mutual electron-nuclear motions in these complexes.

Reactions of Primary Amines with (.eta.5-Pentadienyl)- and (.eta.5-Methylpentadienyl)tricarbonylmanganese Complexes. Synthesis, Characterization, and Structural Studies

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactions of Primary Amines with (.eta.5-Pentadienyl)- and (.eta.5-Methylpentadienyl)tricarbonylmanganese Complexes. Synthesis, Characterization, and Structural StudiesM. Angeles Paz-Sandoval, Rosalina Sanchez Coyotzi, Noe Zuniga Villareal, Richard D. Ernst, and Atta M. ArifCite this: Organometallics 1995, 14, 2, 1044–1052Publication Date (Print):February 1, 1995Publication History Published online1 May 2002Published inissue 1 February 1995https://doi.org/10.1021/om00002a060RIGHTS & PERMISSIONSArticle Views69Altmetric-Citations11LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (967 KB) Get e-AlertsSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts

The synthesis and electrophilic reactivity of manganese tricarbonyl complexes of the C-ring aromatic diterpenoid methyl O-methylpodocarpate

The aromatic ring in the diterpenoid methyl O-methylpodocarpate (podo) coordinates readily to the Mn(CO) 3 + moiety to afford in high yield a nearly 1:1 isometric distribution of [( η 6-podo)Mn(CO) 3] BF 4 ([ 2]BF 4), in which the metal is situated on the α or β face. The nucleophiles PhLi, PhMgBr, MeLi, MeMgCl, LiCH 2C(O)CMe 3 and NaBH 4 were found to add cleanly to the activated aromatic ring in 2 + to give neutral cyclohexadienyl complexes. Nucleophilic addition occurs predominantly meta to the OMe substituent in the case of the α-isomer of 2 +, and at both ortho and meta sites in the case of the β-isomer. The X-ray structure is reported for a typical α- meta and a typical β- ortho cyclohexadienyl product, namely β-( η 5-podo · Ph)Mn(CO) 3 and α-( η 5-podo · CH 2C(O)CMe 3)Mn(CO) 3. The high yield and regioselectivity of the nucleophilic additions suggests that the manganese-mediated functionalization of aromatic diterpenes and steroids will prove to provide a useful synthetic methodology.

Synthesis, characterization and physical properties of tricarbonylmanganese and pentamethylcyclopentadienylcobalt complexes of poly(9-hexylfluorene)

Transition-metal complexes of a conducting polymer, poly(9-hexylfluorene)(abbreviated as PHF), have been prepared and their electrochemical and optical properties investigated. A manganese complex, [Mn(CO)3PHF], is oxidized quasi-reversibly in Bu4NBF4–CF3CO2H at a more negative potential than free PHF, whereas a cobalt complex, [Co(C5Me5)PHF]Clx, is oxidized irreversibly without forming a polaronic state. The photoluminescence intensity of PHF is decreased by coordination to the metals.

Observations on selectivity reversal during chiral auxiliary-directed asymmetric nucleophile additions to arene–manganese tricarbonyl complexes

A study of hydride nucleophile reactions with η6-(2R, 5R)-dimethylpyrrolidinylbenzene–manganese tricarbonyl hexafluorophosphate 1 reveals an unexpected reversal of selectivity during addition of hydride to the diastereotopic meta carbons, which is explained on the basis of changes in transition state location as the reactivity of the nucleophile is varied.

(Arene)tricarbonylmanganese(I) Complexes: a Preparative Study. Crystal Structure of [(.eta.6-C6H5CH2COCH2Ph)Mn(CO)3]BF4

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT(Arene)tricarbonylmanganese(I) Complexes: a Preparative Study. Crystal Structure of [(.eta.6-C6H5CH2COCH2Ph)Mn(CO)3]BF4J. Derek Jackson, Sharon J. Villa, Deborah S. Bacon, Robert D. Pike, and Gene B. CarpenterCite this: Organometallics 1994, 13, 10, 3972–3980Publication Date (Print):October 1, 1994Publication History Published online1 May 2002Published inissue 1 October 1994https://doi.org/10.1021/om00022a037RIGHTS & PERMISSIONSArticle Views485Altmetric-Citations44LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

The synthesis and reactions of A-ring aromatic steroid complexes of manganese tricarbonyl

Treatment of the A-ring aromatic steroids estrone 3-methyl ether and β-estradiol 3, 17-dimethyl ether with Mn(CO) 5 +BF 4 − in CH 2Cl 2 yields the corresponding [(steroid)Mn(CO) 3]BF 4 salts 1 and 2 as mixtures of α and β isomers. The X-ray structure of [(estrone 3-methyl ether)Mn(CO) 3]BF 4 · CH 2Cl 2 ( 1) having the Mn(CO) 3 moiety on the α side of the steroid is reported: space group P2 1 with a=10.3958(9), b=10.9020(6), c=12.6848(9) Å, β=111.857(6)°, Z=2, V=1334.3(2) Å 3, ϱ calc=.481 cm −3, R=0.0508, and wR=0.0635. The molecule has the traditional ‘piano stool’ structure with a planar arene ring and linear MnCO linkages. The nucleophiles NaBH 4 and LiCH 2C(O)CMe 3 add to [(β-estradiol 3,17-dimethyl ether)Mn(CO) 3]BF 4 ( 2) in high yield to give the corresponding α- and β-cyclohexadienyl manganese tricarbonyl complexes ( 3). The nucleophiles add meta to the arene -OMe substituent and exo to the metal. The α and β isomers of 3 were separated by fractional crystallization and the X-ray structure of the β isomer with an exo-CH 2C(O)CMe 3 substituent is reported (complex 4): space group P2 12 12 1 with a=7.5154(8), b=15.160(2), c=25.230(3) Å, Z=4, V=2874.4(5) Å 3, ϱ calc=1.244 g cm −3, R=0.0529 and wR2=0.1176. The molecule 4 has a planar set of dienyl carbon atoms with the saturated C(1) carbon being 0.592 Å out of the plane away from the metal. The results suggest that the manganese-mediated functionalization of aromatic steroids is a viable synthetic procedure with a range of nucleophiles of varying strengths.

ChemInform Abstract: Chiral Auxiliary‐Directed Asymmetric Nucleophile Additions to Arene‐ Manganese Tricarbonyl Complexes.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Reaction of (.eta.5-pentadienyl)tricarbonylmanganese with secondary amines. Synthesis and characterization of (1-amino-.eta.3-pentenyl)tricarbonylmanganese complexes and their phosphine or tetracarbonyl derivatives

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReaction of (.eta.5-pentadienyl)tricarbonylmanganese with secondary amines. Synthesis and characterization of (1-amino-.eta.3-pentenyl)tricarbonylmanganese complexes and their phosphine or tetracarbonyl derivativesN. Zuniga Villarreal, M. A. Paz-Sandoval, P. Joseph-Nathan, and R. O. EsquivelCite this: Organometallics 1991, 10, 8, 2616–2625Publication Date (Print):August 1, 1991Publication History Published online1 May 2002Published inissue 1 August 1991https://doi.org/10.1021/om00054a022RIGHTS & PERMISSIONSArticle Views63Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts