On the scope, mechanism and stereochemistry of the Lewis acid catalyzed cyclocondensation of activated dienes with aldehydes: an application to the erythronolide problem
Stereochemical consequences of the Lewis acid catalyzed cyclocondensation of oxygenated dienes with aldehydes. A rapid and stereoselective entry to various natural products derived from propionate
The reaction of crotyltrialkylstannanes (1) with aldehydes in the presence of BF3,OEt2, produces the corresponding erythro homoallyl alcohols (2) predominantly regardless of the geometry of the double bond. Further, the Lewis acid mediated reaction exhibits the enhanced Cram selectivity in comparison with other allylic organometallic reactions which proceed in the absence of Lewis acids. Use of AlCl3-i-PrOH
Acyclic stereoselection via cyclic hydroboration. Synthesis of the Prelog-Djerassi lactonic acid.
作者:W.Clark Still、Kenneth R. Shaw
DOI:10.1016/s0040-4039(01)82004-9
日期:1981.1
An intramolecularly directed hydroboration (4→5) provides high asymmetric induction for the construction of 1.
分子内定向硼氢化(4→5)为1的构建提供了高度的不对称诱导。
1,2 Asymmetric induction in the cyclic hydroboration of 1,5-dienes. A synthesis of the Prelog-Djerassi lactone
作者:David J. Morgans
DOI:10.1016/s0040-4039(01)82003-7
日期:1981.1
Cyclic hydroboration of an appropriately substituted 1,5-diene yields a 1,5 diol as the major product which can be converted to the racemic Prelog-Djerassilactone.
Obtention de la lactone de prelog-djerassi et d'autres δ-lactones par addition du pentenyltrimethylsilane sur des derives de l'anhydride glutarique
作者:par Christiane Santelli-Rouvier
DOI:10.1016/s0040-4039(01)81441-6
日期:1984.1
Addition of trans-3-trimethylsilyl-pent-2-ene to derivatives of glutaric anhydride and meso-2,4-dimethylglutaric anhydride leads to precursors of the PRELOG-DJERASSI lactone and related δ-lactones.
Stereocontrol in organic synthesis using silicon-containing compounds. A synthesis of the (±)-Prelog–Djerassi lactone
作者:Hak-Fun Chow、Ian Fleming
DOI:10.1039/a804270e
日期:——
β-silyl ester, the enolate alkylation 11→12 of a β-silyl ester, silyl-to-hydroxy conversion with retention of configuration 13→14, and stereospecifically anti protodesilylation of the allylsilanes 26 and 27 giving largely the alkene 28. These allylsilanes had themselves been prepared in a stereocontrolled, convergent synthesis from the allylic acetates 24 and 25, providing thereby a general solution to the