124292-39-3Relevant articles and documents
Reaction of Phenyl-substituted Allyl-lithiums with Secondary Alkyl Halides. A Polar Process versus Single-electron Transfer
Tanaka, Jiro,Morishita, Hiroaki,Nojima, Masatomo,Kusabayashi, Shigekazu
, p. 1009 - 1014 (2007/10/02)
The reaction of 1-phenylallyl-lithium (1a) with optically active 2-halobutanes in ether in the presence of tetramethylethylenediamine or hexamethylphosphoramide gives exclusively 4-methyl-3-phenylhex-1-ene (5a) (coupling at the phenyl-substituted site) with essentially 100percent inversion of configuration.In contrast, treatment of 1,1-diphenylallyl-lithium (1b) with (-)-2-halobutanes under the same conditions results in the formation of a mixture of 4-methyl-3,3-diphenylhex-1-ene (5b) (coupling at C-1) and 4-methyl-1,1-diphenylhex-1-ene (6b) (coupling) at C-3).Moreover, C-C bond formation at the 1-position to provide (5b) is also found to proceed with complete inversionof configuration, while a small but significant loss of stereochemical integrity is observed in the case of the C-3 attack product (6b).These results suggest that a polar pathway should predominate for the formation of the C-1 attack products (5a,b), while competition between polar and single-electron-transfer processes occurs for the formation of the C-3 attack product (6b).
