Total Synthesis of Sedum Alkaloids via Catalyst Controlled aza-Cope Rearrangement and Hydroformylation with Formaldehyde
摘要:
The catalytic asymmetric aminoallylation of chiral aldehydes is developed as a new method for the catalyst controlled synthesis of syn- and anti-1,3-aminoalcohols. This methodology is highlighted in the synthesis of the sedum alkaloids (+)-sedridine and (+)-allosedridine both of which have their final carbon incorporated during closure of the piperidine ring via a hydroformylation with formaldehyde.
Total Synthesis of Sedum Alkaloids via Catalyst Controlled aza-Cope Rearrangement and Hydroformylation with Formaldehyde
摘要:
The catalytic asymmetric aminoallylation of chiral aldehydes is developed as a new method for the catalyst controlled synthesis of syn- and anti-1,3-aminoalcohols. This methodology is highlighted in the synthesis of the sedum alkaloids (+)-sedridine and (+)-allosedridine both of which have their final carbon incorporated during closure of the piperidine ring via a hydroformylation with formaldehyde.
Highly selective enolization method for heteroatom substituted esters; its application to the ireland ester enolate claisen rearrangement
作者:Kouji Hattori、Hisashi Yamamoto
DOI:10.1016/s0040-4020(01)81109-1
日期:1994.3
A method for the stereoselective synthesis of silylketeneacetals from α-siloxy esters, β-hydroxy esters, and α-aminoesters is described. Internal quench with excess trimethylsilyl chloride of the lithium enolate at −100 °C, which is generated using a hindered base, LTMP, leads to the selective formation of E-silyl keteneacetal. In contrast, the deprotonation at −100 °C using LHMDS in THF-HMPA (4:1)