[56161-51-4] · C11H14O4S · 3-(Phenylsulfonyl)propanal Ethylene Acetal · (MW 242.32)
(synthetic reagent for 2-alkenals, 4-oxoalkanals, and 5-hydroxyalkanals)
Form Supplied in: colorless crystals.
Monoalkylation of 3-(phenylsulfonyl)propanal ethylene acetal (1) takes place at the position a to the phenylsulfonyl group on successive treatment with n-Butyllithium and then with an alkyl halide. Deprotection of the acetal group and subsequent elimination of benzenesulfinic acid with a base produces the corresponding 2-alkenal (eq 1).1
A second alkylation is also possible by treatment with alkyl iodide and n-BuLi. Acidic deprotection of the dialkylated product gives the corresponding 2-alkenal (eq 2).1
The lithio derivative of (1) can be acylated with a methyl ester to afford an acylated product which easily undergoes reductive desulfurization with Aluminum Amalgam or Sodium Amalgam to produce a 4-oxoalkanal ethylene acetal, an important synthetic precursor (eq 3).3,4
The lithio derivative of (1) reacts with terminal epoxides to give ring-opened products. Reductive desulfurization followed by acidic deprotection forms 5-hydroxyalkanal, which cyclizes to give a d-lactol (eq 4).5
Lithiated (1) adds to aldehydes. After acetylation, treatment of the adduct with Potassium t-Butoxide causes elimination of benzenesulfinic acid and acetic acid to form an acetal having a triple bond or a conjugated double bond, depending on circumstances (eqs 5 and 6).6,7
4-Phenylsulfonyl-2-butanone Ethylene Acetal.
Chiba University, Japan