Metal-dependent stabilization of Si-S bonds to hydrolysis in iridium and rhodium silyls. Hydrolyzability as a probe for Si-H reductive elimination

Michael Aizenberg, Roman Goikhman, David Milstein

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The iridium (triethylthio) silyl complexes cis(PPh3)2(CO)IrH2(Si(SEt)3) (5), fac-(PMe3)3Ir(CH3(H)-(Si(SEt)3) (6), and mer-(PMe3)3Ir(C6F5)(H)(Si(SEt) 3) (7) were synthesized by oxidative addition of HSi(SEt)3 (1) to HIr(CO)(PPh3)3 (2), CH3Ir(PMe3)4 (3), and C6F5-Ir(PMe3)3 (4), respectively. 4 was synthesized by the reaction between Ir(PMe3)4Cl and C6F5MgBr. The rhodium analog of 7, mer-(PMe3)3Rh(C6F5)(H)(Si(SEt) 3) (9), was obtained similarly from C6F5Rh(PMe3)3, (8) and 1. Unlike the extremely easily hydrolyzable parent silane 1, compounds 5-7 are stable in H2O/THF and even in NaOH/H2O/THF solutions. This stabilization is attributed to the electron-donating capacity of the Ir centers, which efficiently reduces electrophilicity of the silicon. Reactivity of the rhodium complex 9 is strikingly different, cleanly producing in the presence of 5 equiv of H2O the ethylthio-complex mer-(PMe3)3Rh(C6F5)(H)(SEt) (10). Compound 10 was identified spectroscopically and was synthesized independently from 8 and HSEt. A plausible scheme accounting for the generation of 10 under the hydrolysis conditions is presented. The observed difference in the reactivities of 5-7 and 9 is explained in terms of their different tendencies to reductively eliminate H-Si(SEt)3.

Original languageEnglish
Pages (from-to)1075-1078
Number of pages4
JournalOrganometallics
Volume15
Issue number3
Publication statusPublished - Feb 6 1996

Fingerprint

Iridium
Rhodium
Carbon Monoxide
iridium
rhodium
hydrolysis
elimination
Hydrolysis
reactivity
Stabilization
stabilization
Metals
Silanes
probes
Silicon
silanes
metals
tendencies
analogs
Electrons

ASJC Scopus subject areas

  • Inorganic Chemistry
  • Organic Chemistry

Cite this

Metal-dependent stabilization of Si-S bonds to hydrolysis in iridium and rhodium silyls. Hydrolyzability as a probe for Si-H reductive elimination. / Aizenberg, Michael; Goikhman, Roman; Milstein, David.

In: Organometallics, Vol. 15, No. 3, 06.02.1996, p. 1075-1078.

Research output: Contribution to journalArticle

@article{0845d3e17a0b484b901c38735b42c53f,
title = "Metal-dependent stabilization of Si-S bonds to hydrolysis in iridium and rhodium silyls. Hydrolyzability as a probe for Si-H reductive elimination",
abstract = "The iridium (triethylthio) silyl complexes cis(PPh3)2(CO)IrH2(Si(SEt)3) (5), fac-(PMe3)3Ir(CH3(H)-(Si(SEt)3) (6), and mer-(PMe3)3Ir(C6F5)(H)(Si(SEt) 3) (7) were synthesized by oxidative addition of HSi(SEt)3 (1) to HIr(CO)(PPh3)3 (2), CH3Ir(PMe3)4 (3), and C6F5-Ir(PMe3)3 (4), respectively. 4 was synthesized by the reaction between Ir(PMe3)4Cl and C6F5MgBr. The rhodium analog of 7, mer-(PMe3)3Rh(C6F5)(H)(Si(SEt) 3) (9), was obtained similarly from C6F5Rh(PMe3)3, (8) and 1. Unlike the extremely easily hydrolyzable parent silane 1, compounds 5-7 are stable in H2O/THF and even in NaOH/H2O/THF solutions. This stabilization is attributed to the electron-donating capacity of the Ir centers, which efficiently reduces electrophilicity of the silicon. Reactivity of the rhodium complex 9 is strikingly different, cleanly producing in the presence of 5 equiv of H2O the ethylthio-complex mer-(PMe3)3Rh(C6F5)(H)(SEt) (10). Compound 10 was identified spectroscopically and was synthesized independently from 8 and HSEt. A plausible scheme accounting for the generation of 10 under the hydrolysis conditions is presented. The observed difference in the reactivities of 5-7 and 9 is explained in terms of their different tendencies to reductively eliminate H-Si(SEt)3.",
author = "Michael Aizenberg and Roman Goikhman and David Milstein",
year = "1996",
month = "2",
day = "6",
language = "English",
volume = "15",
pages = "1075--1078",
journal = "Organometallics",
issn = "0276-7333",
publisher = "American Chemical Society",
number = "3",

}

TY - JOUR

T1 - Metal-dependent stabilization of Si-S bonds to hydrolysis in iridium and rhodium silyls. Hydrolyzability as a probe for Si-H reductive elimination

AU - Aizenberg, Michael

AU - Goikhman, Roman

AU - Milstein, David

PY - 1996/2/6

Y1 - 1996/2/6

N2 - The iridium (triethylthio) silyl complexes cis(PPh3)2(CO)IrH2(Si(SEt)3) (5), fac-(PMe3)3Ir(CH3(H)-(Si(SEt)3) (6), and mer-(PMe3)3Ir(C6F5)(H)(Si(SEt) 3) (7) were synthesized by oxidative addition of HSi(SEt)3 (1) to HIr(CO)(PPh3)3 (2), CH3Ir(PMe3)4 (3), and C6F5-Ir(PMe3)3 (4), respectively. 4 was synthesized by the reaction between Ir(PMe3)4Cl and C6F5MgBr. The rhodium analog of 7, mer-(PMe3)3Rh(C6F5)(H)(Si(SEt) 3) (9), was obtained similarly from C6F5Rh(PMe3)3, (8) and 1. Unlike the extremely easily hydrolyzable parent silane 1, compounds 5-7 are stable in H2O/THF and even in NaOH/H2O/THF solutions. This stabilization is attributed to the electron-donating capacity of the Ir centers, which efficiently reduces electrophilicity of the silicon. Reactivity of the rhodium complex 9 is strikingly different, cleanly producing in the presence of 5 equiv of H2O the ethylthio-complex mer-(PMe3)3Rh(C6F5)(H)(SEt) (10). Compound 10 was identified spectroscopically and was synthesized independently from 8 and HSEt. A plausible scheme accounting for the generation of 10 under the hydrolysis conditions is presented. The observed difference in the reactivities of 5-7 and 9 is explained in terms of their different tendencies to reductively eliminate H-Si(SEt)3.

AB - The iridium (triethylthio) silyl complexes cis(PPh3)2(CO)IrH2(Si(SEt)3) (5), fac-(PMe3)3Ir(CH3(H)-(Si(SEt)3) (6), and mer-(PMe3)3Ir(C6F5)(H)(Si(SEt) 3) (7) were synthesized by oxidative addition of HSi(SEt)3 (1) to HIr(CO)(PPh3)3 (2), CH3Ir(PMe3)4 (3), and C6F5-Ir(PMe3)3 (4), respectively. 4 was synthesized by the reaction between Ir(PMe3)4Cl and C6F5MgBr. The rhodium analog of 7, mer-(PMe3)3Rh(C6F5)(H)(Si(SEt) 3) (9), was obtained similarly from C6F5Rh(PMe3)3, (8) and 1. Unlike the extremely easily hydrolyzable parent silane 1, compounds 5-7 are stable in H2O/THF and even in NaOH/H2O/THF solutions. This stabilization is attributed to the electron-donating capacity of the Ir centers, which efficiently reduces electrophilicity of the silicon. Reactivity of the rhodium complex 9 is strikingly different, cleanly producing in the presence of 5 equiv of H2O the ethylthio-complex mer-(PMe3)3Rh(C6F5)(H)(SEt) (10). Compound 10 was identified spectroscopically and was synthesized independently from 8 and HSEt. A plausible scheme accounting for the generation of 10 under the hydrolysis conditions is presented. The observed difference in the reactivities of 5-7 and 9 is explained in terms of their different tendencies to reductively eliminate H-Si(SEt)3.

UR - http://www.scopus.com/inward/record.url?scp=0037611473&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037611473&partnerID=8YFLogxK

M3 - Article

VL - 15

SP - 1075

EP - 1078

JO - Organometallics

JF - Organometallics

SN - 0276-7333

IS - 3

ER -