Syntheses and reactivities of osmium and ruthenium complexes with metal-carbon triple bonds

Abstract

Treatment of Os (=CAr-η2-CH=C=CHAr)CI2(PPh3)2 with Au(C≡CR)(PPh3)(R = Ph, p-tolyl, n-butyl, SiMe3) led to the formation of the osmabenzyne complexes OS(≡CCR=C(CH2Ar)CH=CAr)Cl2(PPh3)2. Treatment of Os(=CPh-η2-CH=C=CHPh)Cl2(PPh3)2 with PhC≡C-C≡CPh gave the fulvene complex OsCl2(η6-C5H(C≡CPh)(Ph)2CHPh)(PPh3). Reaction of Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)Cl2(PPh3)2 with TlOTf afforded the cationic osmabenzyne [Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)CI(H2O)(PPh3)2]OTf, which can undergo ligand substitution with PMe3 and 2,2'-bipyridine to produce [Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)Cl(PMe3)(PPh3)2]OTf and [Os(≡CC(SiMe3)=C(Me)C(SiMe3)=CH)(bipy)(PPh3)2](OTf)2, respectively. Treatment of Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)Cl2(PPh3)2 and Os(≡CCH=C(CH3)CH=CH)CI2(PPh3)2 with bromine produced the same osmabenzyne Os(≡CC(Br)=C(CH3)C(Br)=CH)Br2(PPh3)2. Nitration of Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)Cl2(PPh3)2 with NO2BF4 and NaCl led to Os(≡CC(SiMe3)=C(CH3)C(NO2)=CH)Cl2(PPh3)2, Os(≡CC(SiMe3)=C(CH3)C(NO)=CH)CI2(PPh3)2, and a paramagnetic complex. Os(≡CC(SiMe3)=C(CH3)C(NO)=CH)CI2(PPh3)2 could also be prepared from the reaction of Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)CI2(PPh3)2 with NOBF4 and NaCI. Reaction of Os(≡CC(SiMe3)=C(CH3)C(SiMe3)=CH)Cl2(PPh3)2 with AICI3/H2O2 produced Os(η2=C(O)CCI=C(CH3)CCI=CH)(PPh3)2CI2 and Os(η2=C(O)CCI=C(CH3)C(SiMe3)=CH)(PPh3)2CI2. Reaction of osmabenzyne Os(≡CC(SiMe3)=C(Me)C(SiMe3)=CH)(bipy)(PPh3)2](OTf)2 with water and methanol produced osmabenzenes [Os(=C(OH)CH=C(CH3)C(SiMe3)=CH)(bipy)(PPh3)2]OTf and [Os=(C(OMe)CH=C(CH3)C(SiMe3)=CH)(bipy)(PPh3)2]OTf repectively. The vinyl complex [Os(CH=C(SiMe3)C(CH3)=CH2)(CO)(bipy)(PPh3)2]OTf was isolated from the reaction of Os(≡CC(SiMe3)=C(Me)C(SiMe3)=CH)(bipy)(PPh3)2](OTf)2 with water. Treatment of Os(≡CC(SiMe3)=C(Me)C(SiMe3)=CH)(bipy)(PPh3)2](OTf)2 with NaBH4 produced the cyclopentadienyl complex [Os(η5-CHCHC(SiMe3)C(CH3)C(SiMe3))(bipy)(PPh3)]OTf. Reaction of mer-[OsCI3(≡CCH=CPh2)(PPh3)2] and fac-[OsCI3(≡CCH=CPh2)(PPh3)2] with primary amines RNH2 (R = CH3CH2, CH3(CH2)3) produced the allenylidene complexes cis- or mer-Os(=C=C=CPh2)CI2(RNH2)(PPh3)2, respectively (R = CH3CH2, CH3(CH2)3). Reaction of mer-[OsCI3(≡CCH=CPh2)(PPh3)2] with tert-butylamine afforded the indenyl complex Os(η5C9H5(tBu)(Ph))(PPh3)2CI. Treatment of mer-[OsCI3(≡CCH=CPh2)(PPh3)2] with diethylamine gave a mixture of allenylidene Os(=C=C=CPh2)CI2(CH3CH2NH2)(PPh3)2 and hydrido-carbyne Os(≡CCH=CPh2) (PPh3)2HCI2. Treatment of mer-[OsCI3(≡CCH=CPh2)(PPh3)2] with the tertiary amine (NH2CH2CH2)3N gave the cationic carbene complex [Os(η3-N(CH2CH2NH2)2CH2CH2NH)(=CCH=CPh2)CI(PPh3)]CI. Reaction of mer-[OsCI3(≡CCH=CPh2)(PPh3)2] with pyridine (py) and 4-picoline (pi) under refluxing condition produced the carbyne complexes Os(≡CCH=CPh2)CI3(PPh3)(py) and Os(≡CCH=CPh2)CI3(PPh3)(pi), respectively. Treatment of mer-[MCI3(≡CCH=CPh2)(PPh3)2] ( M = Os, Ru) with zinc powder in the presence of PPh3 led to the reduction of the carbyne complex to give indenyl-complexes M(η5C9H7(Ph))(PPh3)2CI (M = Os, M = Ru). The ruthenium carbyne complexes mer-[RuCI3(≡CCH=CRR')(PPh3)2] were prepared conveniently from a one-pot reaction of RuCI2(PPh3)3 with HC≡CCH(OH)RR' in the presence of HCI (R, R' = Ph, CH3). Treatment of mer-OsCI3(≡CCH2Ph)(PPh3)2 with zinc powder and PPh3 in refluxing THF solution afforded the hydrido-vinylidene complex OsHCI(=C=CHPh)(PPh3)3. Reaction of mer-OsCI3(≡CCH2Ph)(PPh3)2 with H2O2 in CH2CI2 produced OsCI3(≡CC(O)Ph)(PPh3)2.

Date of Award	2006
Original language	English
Awarding Institution	The Hong Kong University of Science and Technology