Nucleophilic addition to vinylketene- and vinylketenimine (allenylideneamine)tricarbonyliron(0) complexes
作者:Lawrence Hill、Christopher J. Richards、Susan E. Thomas
DOI:10.1039/c39900001085
日期:——
Nucleophiles add to C-1 of (vinylketene)tricarbonyliron(0) complexes to give β,γ-unsaturated carbonyl derivatives, whereas nucleophilic attack on a (vinylketenimine)tricarbonyliron(0) analogue occurs at C-2 and leads, after an oxidative work-up, to β,γ-unsaturated amides containing an a quaternary centre.
Nucleophilic addition to vinylketenimine complexes. The asymmetric synthesis of carbon quaternary centres
作者:Christopher J. Richards、Susan E. Thomas
DOI:10.1016/s0957-4166(00)82321-6
日期:1992.1
Addition of alkyl-lithium reagents to (vinylketenimine)tricarbonyliron(0) complexes generates compounds containing carbon quaternary centres. The major products from these reactions are either amides or aldehydes depending upon the conditions employed. Diastereomerically pure vinylketenimine complexes 7 and 8 of known absolute configuration were synthesised from (S)-alpha-methylbenzylisonitrile 6 (96% e.e.) and the (vinylketene)tricarbonyliron(0) complex 2. The addition of alkyl-lithium reagents to 7 and 8 occurred exclusively exo to the Fe(CO)3 group and the resulting compounds, which contained chiral quaternary centres, were found to be of high optical purity.