Stereoselective enol tosylation: preparation of trisubstituted alpha,beta-unsaturated esters.
[Reaction: see text] The stereoselective preparation of (E)- or (Z)-trisubstituted alpha,beta-unsaturated esters in three steps from N-protected glycine is presented. The key step in the synthesis is the highly selective enol tosylation of gamma-amino beta-keto esters. The enol tosylates are stable, crystalline compounds that undergo smooth and effective Suzuki-Miyaura coupling reaction with a variety of aryl boronic acids.
Baxter
Jenny M
JM
Department of Process Research, Merck & Co., Inc., P.O. Box 2000, Rahway, New Jersey 07065, USA. jenny_baxter@merck.com
Steinhuebel
Dietrich
D
Palucki
Michael
M
Davies
Ian W
IW
D000447:Aldehydes / Q000737:chemistry*; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D005998:Glycine / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism; D014105:Tosyl Compounds / Q000737:chemistry*; D005680:gamma-Aminobutyric Acid / Q000737:chemistry
D000447:Aldehydes; D004952:Esters; D007659:Ketones; D014105:Tosyl Compounds; D005680:gamma-Aminobutyric Acid; D005998:Glycine