A practical procedure of low valent tin mediated Barbier allylation of aldehydes in wet solvent

Use of aluminium as the reducing metal in spontaneous bimetal redox reaction has been elegantly exploited for allylation/crotylation of aldehydes in wet solvent. Here, low valent tin was prepared in situ by reduction of SnCl2·2H2O with aluminium in THF/water. The resulting low valent tin acted as an efficient mediator for allylation and crotylation of aldehydes (3a–q) producing the corresponding homoallylic alcohols. The efficacy of this procedure was due to its operational simplicity, practical viability, inexpensiveness, good yields of the products and short reaction time.