Stereoselective cyclic carbolithiation of alkyne derivatives. A stereoselective synthesis of exocyclic alkenes
作者:Guangzhong Wu、Fredrick E Cederbaum、Ei-ichi Negishi
DOI:10.1016/0040-4039(90)87016-s
日期:1990.1
(Trimethylsilyl)alkyne derivatives that are lithiated in the δ position via non-radical routes can cyclize in a stereoselective manner (≥96-98%) to give exocyclic alkenes containing five-membered carbocycles in high yields.
Cycloisomerization of Acetylenic Vinyllithiums: Sequential Anionic Cyclization-Cycloaddition as a Route to Polycyclic Ring Systems
作者:Timo V. Ovaska、Rachel R. Warren、Carl E. Lewis、Nanette Wachter-Jurcsak、William F. Bailey
DOI:10.1021/jo00099a010
日期:1994.10
Acetylenic vinyllithiums, generated by low-temperature metal-halogen exchange, were found to undergo facile 5-exo-dig cyclization to afford isomerically pure conjugated 1,3-bis-exocyclic dienes which serve as reactive precursors to complex polycyclic materials through subsequent Diels-Alder methodology.
WU, GUANGZHONG;CEDERBAUM, FREDRICK E.;NEGISHI, EI-ICHI, TETRAHEDRON LETT., 31,(1990) N, C. 493-496