%0 Journal Article
%A Itazaki, Masumi
%A Yoda, Chikako
%A Nishihara, Yasushi
%A Osakada, Kohtaro
%D 2004
%T C−C and C−H Bond Activation of
Dialkylmethylenecyclopropane Promoted by Rhodium
and Iridium Complexes. Preparation and Structures of
M(η1:η2-CH2CR2CHCH2)(CO)(PPh3)2 and
trans-M(CHCHCMeR2)(CO)(PPh3)2 (M = Rh, Ir, R =
CH2CH2Ph)
%U https://acs.figshare.com/articles/journal_contribution/C_C_and_C_H_Bond_Activation_of_Dialkylmethylenecyclopropane_Promoted_by_Rhodium_and_Iridium_Complexes_Preparation_and_Structures_of_M_sup_1_sup_sup_2_sup_CH_sub_2_sub_CR_sub_2_sub_CH_CH_sub_2_sub_CO_PPh_sub_3_sub_sub_2_sub_and_i_trans_i_M_CH_CHCMeR_sub_2_/3317173
%R 10.1021/om049632a.s001
%2 https://acs.figshare.com/ndownloader/files/5155906
%K reaction mechanisms
%K Dialkylmethylenecyclopropane Promoted
%K alkenyl complexes trans
%K Heating 1
%K HC
%K H 2
%K MH
%K Iridium Complexes
%K η 2
%K CO
%K 2 CH 3
%K CR
%K NMR
%K η 1
%K oxidative addition
%K alkynyl complexes trans
%K metal center
%K room temperature
%K CH 2 CH 2 Ph
%X 2,2-Bis(2-phenylethyl)-1-methylenecyclopropane reacts with RhH(CO)(PPh3)3 at room
temperature and with IrH(CO)(PPh3)3 at 70 °C to form the 3-butenyl complexes of these
metals, M{η1:η2-CH2C(CH2CH2Ph)2CHCH2}(CO)(PPh3)2 (1, M = Rh; 2, M = Ir). Heating 1
at 55 °C liberates 1,1-bis(2-phenylethyl)-1,3-butadiene, while the thermal reaction of 2 at
110 °C forms a mixture of 3-methyl-3-vinyl-1,5-diphenyl-1-pentene (48% NMR yield) and
3-methyl-3-vinyl-1,5-diphenylpentane (15% NMR yield). The reactions of excess amounts of
2,2-bis(2-phenylethyl)-1-methylenecyclopropane with RhH(CO)(PPh3)3 at 55 °C and with IrH(CO)(PPh3)3 at 115 °C afford the alkenyl complexes trans-Rh{(Z)-CHCHC(CH2CH2Ph)2CH3}(CO)(PPh3)2 (3) and trans-Ir{(E)-CHCHC(CH2CH2Ph)2CH3}(CO)(PPh3)2 (4), respectively.
The reaction mechanisms are discussed on the basis of the results of the reactions under
different conditions. HC⋮CC(CH2CH2Ph)2CH3 reacts with MH(CO)(PPh3)3 (M = Rh, Ir) to
afford the alkynyl complexes trans-M{C⋮CC(CH2CH2Ph)2CH3}(CO)(PPh3)2 (5, M = Rh; 6,
M = Ir) via oxidative addition of the C(alkyne)−H bond to the metal center and subsequent
elimination of H2.
%I ACS Publications