Sequential Knoevenagel Reaction/Mislow-Evans Rearrangement Catalyzed by Heterogeneous Amine Grafted on Silica in Water, Leading to (gamma)-Hydroxy-(alpha),?-unsaturated Nitrile

(gamma)-Hydroxy-(alpha),?-unsaturated nitrile was obtained by the reaction of (alpha)-arylsulfinylacetonitrile with aldehyde in water, which was catalyzed by N,N-diethylaminopropylated silica gel. The overall transformation proceeded via five sequential reactions, 1,2-addition of acetonitrile, dehydration (Knoevenagel condensation), isomerization of the double bond, rearrangement of sulfinyl group (Mislow-Evans rearrangement) and hydrolysis of sulfinyl ester. The reaction condition was mild such that the AcO, TBMDSO or OTHP group remained intact in the products.