Substitution of P(O)Ph2, SOPh and SO2Ph on an allene facilitates intramolecular radical addition to the central allene carbon to provide good yields of five-, six-, and seven-membered carbocycles.
Stereoselectivity in the photoinduced electron transfer (PET) promoted intramolecular cyclisations of 1-alkenyl-2-silyl-piperidines and -pyrrolidines: rapid construction of 1-azabicyclo[m.n.0]alkanes and stereoselective synthesis of (±)-isoretronecanol and (±)-epilupinine
PET promoted cyclisations of 1-alkenyl-2-silyl-pyrrolidines and -piperidines 9a-d to 1-aza-bicyclo[m.n.0]alkanes have been found to be stereoselective. The five-membered ring formation gives predominantly cis products while six-membered rings are trans. Application of such cyclisations to the synthesis of (+/-)-isoretronecanol 22a, (+/-)-epilupinine 29 and related alkaloids has been demonstrated.
PATTERSON, J. W. ,, JR.;PFISTER, J. R.
作者:PATTERSON, J. W. ,, JR.、PFISTER, J. R.
DOI:——
日期:——
US4515727A
申请人:——
公开号:US4515727A
公开(公告)日:1985-05-07
Radical cyclizations of functionalized allenes
作者:Jack K. Crandall、Timothy A. Ayers
DOI:10.1016/s0040-4039(00)79759-0
日期:1991.7
Substitution of P(O)Ph2, SOPh and SO2Ph on an allene facilitates intramolecular radical addition to the central allene carbon to provide good yields of five-, six-, and seven-membered carbocycles.