Lewis base catalyzed 1,3-dithiane addition to carbonyl compounds using 2-trimethylsilyl-1,3-dithiane

1,3-Dithiane addition to various aldehydes and ketones using 2-trimethylsilyl-1,3-dithiane in the presence of a catalytic amount of a Lewis base such as tetrabutylammonium phenoxide (PhONn-Bu-4) proceeds smoothly to afford the corresponding alpha-hydroxy dithiane compounds in good to high yields under mild conditions.