(+/-)-erythro-γ,δ-Dihydroxycarboxylic Acid Lactones from a β-Lithiopropionate Equivalent and α-Chloroaldehydes

Article abstract of DOI:10.1055/s-1989-27308

Reaction of β-ethylthio-β-lithioacrylate 1A with α-chloroaldehydes furnished predominantly the erythro products 3, which were isolated as γ-lactones 4.At room temperature intermediates 3 are transformed into the (+/-)-erythro-γ,δ-dihydroxycarboxylic acid γ-lactones 8.Raney nickel treatment provided interesting natural γ-lactone derivatives; thus, from erythro-8c the socalled L-factor erythro-9c was obtained.Similarly, from β-methoxy β-lithioacrylate 10A the (+/-)-erythro-γ,δ-dihydroxycarboxylic acid δ-lactone erythro-11 was gained.