Highly Stereocontrolled Cyclopropanation by the 1,3-Elimination of a Bis(tributylstannyl)propanol Derivative.
The highly stereoselective ring closure of gamma-hydroxystannyl derivative was realized. The aldol reaction of methyl bis(tributylstannyl)propionate (2) with aldehyde 5 proceeds stereoselectively to give (gamma-hydroxypropyl)stannane 6, and the cyclopropanation reaction of aldol product 6 proceeds smoothly in a highly stereoselective manner presumably via a W-shape transition state. The stannyl group on the cyclopropane ring can be converted into various electrophiles with a retention of configuration. As a result, various stereocontrolled 1,2,3-trisubstituted cyclopropanes can be obtained in high yields.
Isono
Naohiro
N
Faculty of Pharmaceutical Sciences, Hokkaido University Sapporo 060, Japan.
Mori
Miwako
M