A novel synthetic method for alkylidenecyclopropanes based on the reaction of magnesium cyclopropylidenes with lithium α-sulfonyl carbanions
作者:Tsuyoshi Satoh、Shinya Saito
DOI:10.1016/j.tetlet.2003.10.162
日期:2004.1
Treatment of 1-chlorocyclopropyl phenyl sulfoxides with isopropylmagnesium chloride at low temperature gave magnesium cyclopropylidenes. The reaction of the generated carbenoids with lithium α-sulfonylcarbanions was found to afford alkylidenecyclopropanes in moderate to good yields. This reaction offers a novel, unprecedented, and versatile method for a synthesis of several alkylidenecyclopropanes from
Organometallic additions to protected quinone bis-epoxides and quinone monoacetals: synthesis of the aranorosin nucleus
作者:Alexander McKillop、Richard J. K. Taylor、Robert J. Watson、Norman Lewis
DOI:10.1039/c39920001589
日期:——
The addition reactions of organometallic reagents to monoprotected quinone bis-epoxides 7 and quinone monoacetals 5 provide a route to the highly oxygenated cyclohexanols 2 and 3; the application of this methodology to the preparation of the aranorosin analogue 4 is described.
A synthesis of (+)-milbemycin β<sub>3</sub>. The directed aldol approach
作者:Stephen D. A. Street、Clive Yeates、Philip Kocienski、Simon F. Campbell
DOI:10.1039/c39850001386
日期:——
A synthesis of (+)-milbemycinβ, is reported in which key steps are the construction of the 1,7-dioxaspiro[5.5]undecane (15) by a Lewis acid-catalysed intramolecular directedaldol reaction and the use of sulphone-based olefination reactions for the construction of the double bonds at C(10)–C(11) and C(14)–C(15).