Acidity-directed synthesis of substituted gamma-butyrolactones from aliphatic aldehydes.
The strength of the Lewis or Brønsted acids controls the formation of either beta,gamma-disubstituted-alpha-methylene-gamma-butyrolactones or gamma-substituted-alpha-alkylidene-gamma-butyrolactones via the lactonization or oxonia cope rearrangement-lactonization, respectively, of the borate intermediates resulting from the crotylboration of aliphatic aldehydes with ester-containing crotylboronates, such as (E)-methyl 2-boramethyl-2-butenoates.
Ramachandran
P Veeraraghavan
PV
Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, USA. chandran@purdue.edu
Pratihar
Debarshi
D