title: Preparation and configurational stability of chiral chloro-[D1]methyllithiums of 98% enantiomeric excess.
abstract: Enantiopure stannyl-[D1]methanol was converted to chloro-[D1]methylstannane under complete inversion of configuration using Ph3P/N-chlorosuccinimide in THF. It was transmetalated to stereospecifically give chloro-[D1]methyllithium (ee up to 98%). Its microscopic configurational stability was tested by performing tin-lithium exchange in the presence of benzaldehyde as the electrophile under various conditions. The macroscopic configurational stability was addressed by using the same electrophile but by adding it 30 s after the addition of MeLi used for transmetalation. Chloro-[D1]methyllithium is chemically very labile, however completely configurationally stable on both time scales up to the temperature of rapid decomposition (-78 degrees C).
authors.affiliation: Institute of Organic Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria.
authors.forename: Dagmar C
authors.initials: DC
authors.lastname: Kapeller
authors.forename: Friedrich
authors.initials: F
authors.lastname: Hammerschmidt