Synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes: First comparative study of the (acylimino)pnictorane series

Y. Matano, H. Nomura, H. Suzuki, M. Shiro, H. Nakano

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

The synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes and a comparative study of the structure and reactivity of a series of (acylimino)pnictoranes are reported. Treatment of ortho-substituted triarylbismuth dichlorides 1 (Ar3BiCl2; Ar = 2-MeC6H4, 2-MeOC6H4, 2,4,6-Me3C6H2) with amides 2 (H2-NCOR; R = CF3, CCl3, 3,5-(CF3)2C6H3) in the presence of 2.2 equiv of KO-t-Bu in dichloromethane afforded (acylimino)triaryl-λ5-bismuthanes 3 (Ar3Bi=NCOR) in yields of 77-96%. The ortho-substituted aryl ligands and the electron-withdrawing N-substituents afford kinetic and thermodynamic stabilization, respectively, to the reactive Bi=N bond. The structures and properties of a series of (acylimino)pnictoranes (Ar3M=NCOR and H3M=NCOCF3; M = P, As, Sb, Bi) are compared by IR and 13C and 15N NMR, X-ray crystallography, and ab initio molecular orbital calculations. It was found that the contribution of the M+-N=C-O- canonical form becomes more prominent and the single-bond character of the M=N bond increases progressively as the pnictogen atom becomes heavier. The Bi=N bond of (acylimino)-λ5-bismuthanes 3 possesses a highly polarized single-bond character, probably due to the differences in orbital size and electronegativity between the bismuth and nitrogen atoms. Thermal decomposition of (aroylimino)triaryl-λ5-bismuthane 3f (o-Tol3Bi=NCOAr; Ar = 3,5-(CF3)2C6H3) produces a gel in dry conditions or aniline 12 (ArNH2) in slightly wet conditions with a good recovery of tris(2-methylphenyl)bismuthane (4a). It is likely that the aryl isocyanate 13 (ArNCO) is produced during the thermolysis via a concerted C → N migration of the Ar group with an elimination of the triarylbismuthonio group as bismuthane 4a. (Acylimino)triaryl-λ5-bismuthanes 3 oxidize 1,1,2,2-tetraphenylethanediol, benzenethiol, methanol, and ethanol to benzophenone, diphenyl disulfide, methyl formate, and acetaldehyde, respectively, in two different reaction pathways depending on the structure of the substrates. Compound 3d (o-Tol3Bi=NCOCCl3) transfers the nitrenoid moiety to triphenylphosphane, triphenylarsane, and tris(2-methylphenyl)stibane to give the corresponding (acylimino)pnictoranes (Ar3M=NCOCl3; M = P, As, Sb) and 4a, suggesting that 3d is thermodynamically much less stable than their lighter pnictogen counterparts. The copper-catalyzed decomposition of 3 (o-Tol3Bi=NCOR) afforded N-acyl-o-toluidines 18 (o-TolNHCOR) via a Bi → N migration of the tolyl group. The observed reactivities of (acylimino)triaryl-λ5-bismuthanes 3 demonstrate a good leaving ability of the bismuthonio group.

Original languageEnglish
Pages (from-to)10954-10965
Number of pages12
JournalJournal of the American Chemical Society
Volume123
Issue number44
DOIs
Publication statusPublished - Nov 7 2001

Fingerprint

2-toluidine
Isocyanates
Orbital calculations
Atoms
Electronegativity
Bismuth
Thermolysis
Acetaldehyde
Methylene Chloride
X ray crystallography
X Ray Crystallography
Dichloromethane
Molecular orbitals
Aniline
Thermodynamics
Amides
Methanol
Copper
Pyrolysis
Ethanol

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes : First comparative study of the (acylimino)pnictorane series. / Matano, Y.; Nomura, H.; Suzuki, H.; Shiro, M.; Nakano, H.

In: Journal of the American Chemical Society, Vol. 123, No. 44, 07.11.2001, p. 10954-10965.

Research output: Contribution to journalArticle

@article{604ddec99b444dbe959d03c978203ff0,
title = "Synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes: First comparative study of the (acylimino)pnictorane series",
abstract = "The synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes and a comparative study of the structure and reactivity of a series of (acylimino)pnictoranes are reported. Treatment of ortho-substituted triarylbismuth dichlorides 1 (Ar3BiCl2; Ar = 2-MeC6H4, 2-MeOC6H4, 2,4,6-Me3C6H2) with amides 2 (H2-NCOR; R = CF3, CCl3, 3,5-(CF3)2C6H3) in the presence of 2.2 equiv of KO-t-Bu in dichloromethane afforded (acylimino)triaryl-λ5-bismuthanes 3 (Ar3Bi=NCOR) in yields of 77-96{\%}. The ortho-substituted aryl ligands and the electron-withdrawing N-substituents afford kinetic and thermodynamic stabilization, respectively, to the reactive Bi=N bond. The structures and properties of a series of (acylimino)pnictoranes (Ar3M=NCOR and H3M=NCOCF3; M = P, As, Sb, Bi) are compared by IR and 13C and 15N NMR, X-ray crystallography, and ab initio molecular orbital calculations. It was found that the contribution of the M+-N=C-O- canonical form becomes more prominent and the single-bond character of the M=N bond increases progressively as the pnictogen atom becomes heavier. The Bi=N bond of (acylimino)-λ5-bismuthanes 3 possesses a highly polarized single-bond character, probably due to the differences in orbital size and electronegativity between the bismuth and nitrogen atoms. Thermal decomposition of (aroylimino)triaryl-λ5-bismuthane 3f (o-Tol3Bi=NCOAr; Ar = 3,5-(CF3)2C6H3) produces a gel in dry conditions or aniline 12 (ArNH2) in slightly wet conditions with a good recovery of tris(2-methylphenyl)bismuthane (4a). It is likely that the aryl isocyanate 13 (ArNCO) is produced during the thermolysis via a concerted C → N migration of the Ar group with an elimination of the triarylbismuthonio group as bismuthane 4a. (Acylimino)triaryl-λ5-bismuthanes 3 oxidize 1,1,2,2-tetraphenylethanediol, benzenethiol, methanol, and ethanol to benzophenone, diphenyl disulfide, methyl formate, and acetaldehyde, respectively, in two different reaction pathways depending on the structure of the substrates. Compound 3d (o-Tol3Bi=NCOCCl3) transfers the nitrenoid moiety to triphenylphosphane, triphenylarsane, and tris(2-methylphenyl)stibane to give the corresponding (acylimino)pnictoranes (Ar3M=NCOCl3; M = P, As, Sb) and 4a, suggesting that 3d is thermodynamically much less stable than their lighter pnictogen counterparts. The copper-catalyzed decomposition of 3 (o-Tol3Bi=NCOR) afforded N-acyl-o-toluidines 18 (o-TolNHCOR) via a Bi → N migration of the tolyl group. The observed reactivities of (acylimino)triaryl-λ5-bismuthanes 3 demonstrate a good leaving ability of the bismuthonio group.",
author = "Y. Matano and H. Nomura and H. Suzuki and M. Shiro and H. Nakano",
year = "2001",
month = "11",
day = "7",
doi = "10.1021/ja003623l",
language = "English",
volume = "123",
pages = "10954--10965",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "44",

}

TY - JOUR

T1 - Synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes

T2 - First comparative study of the (acylimino)pnictorane series

AU - Matano, Y.

AU - Nomura, H.

AU - Suzuki, H.

AU - Shiro, M.

AU - Nakano, H.

PY - 2001/11/7

Y1 - 2001/11/7

N2 - The synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes and a comparative study of the structure and reactivity of a series of (acylimino)pnictoranes are reported. Treatment of ortho-substituted triarylbismuth dichlorides 1 (Ar3BiCl2; Ar = 2-MeC6H4, 2-MeOC6H4, 2,4,6-Me3C6H2) with amides 2 (H2-NCOR; R = CF3, CCl3, 3,5-(CF3)2C6H3) in the presence of 2.2 equiv of KO-t-Bu in dichloromethane afforded (acylimino)triaryl-λ5-bismuthanes 3 (Ar3Bi=NCOR) in yields of 77-96%. The ortho-substituted aryl ligands and the electron-withdrawing N-substituents afford kinetic and thermodynamic stabilization, respectively, to the reactive Bi=N bond. The structures and properties of a series of (acylimino)pnictoranes (Ar3M=NCOR and H3M=NCOCF3; M = P, As, Sb, Bi) are compared by IR and 13C and 15N NMR, X-ray crystallography, and ab initio molecular orbital calculations. It was found that the contribution of the M+-N=C-O- canonical form becomes more prominent and the single-bond character of the M=N bond increases progressively as the pnictogen atom becomes heavier. The Bi=N bond of (acylimino)-λ5-bismuthanes 3 possesses a highly polarized single-bond character, probably due to the differences in orbital size and electronegativity between the bismuth and nitrogen atoms. Thermal decomposition of (aroylimino)triaryl-λ5-bismuthane 3f (o-Tol3Bi=NCOAr; Ar = 3,5-(CF3)2C6H3) produces a gel in dry conditions or aniline 12 (ArNH2) in slightly wet conditions with a good recovery of tris(2-methylphenyl)bismuthane (4a). It is likely that the aryl isocyanate 13 (ArNCO) is produced during the thermolysis via a concerted C → N migration of the Ar group with an elimination of the triarylbismuthonio group as bismuthane 4a. (Acylimino)triaryl-λ5-bismuthanes 3 oxidize 1,1,2,2-tetraphenylethanediol, benzenethiol, methanol, and ethanol to benzophenone, diphenyl disulfide, methyl formate, and acetaldehyde, respectively, in two different reaction pathways depending on the structure of the substrates. Compound 3d (o-Tol3Bi=NCOCCl3) transfers the nitrenoid moiety to triphenylphosphane, triphenylarsane, and tris(2-methylphenyl)stibane to give the corresponding (acylimino)pnictoranes (Ar3M=NCOCl3; M = P, As, Sb) and 4a, suggesting that 3d is thermodynamically much less stable than their lighter pnictogen counterparts. The copper-catalyzed decomposition of 3 (o-Tol3Bi=NCOR) afforded N-acyl-o-toluidines 18 (o-TolNHCOR) via a Bi → N migration of the tolyl group. The observed reactivities of (acylimino)triaryl-λ5-bismuthanes 3 demonstrate a good leaving ability of the bismuthonio group.

AB - The synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes and a comparative study of the structure and reactivity of a series of (acylimino)pnictoranes are reported. Treatment of ortho-substituted triarylbismuth dichlorides 1 (Ar3BiCl2; Ar = 2-MeC6H4, 2-MeOC6H4, 2,4,6-Me3C6H2) with amides 2 (H2-NCOR; R = CF3, CCl3, 3,5-(CF3)2C6H3) in the presence of 2.2 equiv of KO-t-Bu in dichloromethane afforded (acylimino)triaryl-λ5-bismuthanes 3 (Ar3Bi=NCOR) in yields of 77-96%. The ortho-substituted aryl ligands and the electron-withdrawing N-substituents afford kinetic and thermodynamic stabilization, respectively, to the reactive Bi=N bond. The structures and properties of a series of (acylimino)pnictoranes (Ar3M=NCOR and H3M=NCOCF3; M = P, As, Sb, Bi) are compared by IR and 13C and 15N NMR, X-ray crystallography, and ab initio molecular orbital calculations. It was found that the contribution of the M+-N=C-O- canonical form becomes more prominent and the single-bond character of the M=N bond increases progressively as the pnictogen atom becomes heavier. The Bi=N bond of (acylimino)-λ5-bismuthanes 3 possesses a highly polarized single-bond character, probably due to the differences in orbital size and electronegativity between the bismuth and nitrogen atoms. Thermal decomposition of (aroylimino)triaryl-λ5-bismuthane 3f (o-Tol3Bi=NCOAr; Ar = 3,5-(CF3)2C6H3) produces a gel in dry conditions or aniline 12 (ArNH2) in slightly wet conditions with a good recovery of tris(2-methylphenyl)bismuthane (4a). It is likely that the aryl isocyanate 13 (ArNCO) is produced during the thermolysis via a concerted C → N migration of the Ar group with an elimination of the triarylbismuthonio group as bismuthane 4a. (Acylimino)triaryl-λ5-bismuthanes 3 oxidize 1,1,2,2-tetraphenylethanediol, benzenethiol, methanol, and ethanol to benzophenone, diphenyl disulfide, methyl formate, and acetaldehyde, respectively, in two different reaction pathways depending on the structure of the substrates. Compound 3d (o-Tol3Bi=NCOCCl3) transfers the nitrenoid moiety to triphenylphosphane, triphenylarsane, and tris(2-methylphenyl)stibane to give the corresponding (acylimino)pnictoranes (Ar3M=NCOCl3; M = P, As, Sb) and 4a, suggesting that 3d is thermodynamically much less stable than their lighter pnictogen counterparts. The copper-catalyzed decomposition of 3 (o-Tol3Bi=NCOR) afforded N-acyl-o-toluidines 18 (o-TolNHCOR) via a Bi → N migration of the tolyl group. The observed reactivities of (acylimino)triaryl-λ5-bismuthanes 3 demonstrate a good leaving ability of the bismuthonio group.

UR - http://www.scopus.com/inward/record.url?scp=0035823874&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035823874&partnerID=8YFLogxK

U2 - 10.1021/ja003623l

DO - 10.1021/ja003623l

M3 - Article

C2 - 11686699

AN - SCOPUS:0035823874

VL - 123

SP - 10954

EP - 10965

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 44

ER -