Selective Reduction of Aromatic Nitriles to Aldehydes by Lithium Diisobutylpiperidinohydroaluminate (LDBPA)

摘要

Partial reduction of nitriles into aldehyde is one of the most important and highly desirable means in organic synthesis,and a large number of reducing agents for this have been reported.1 Among them,a commercially available diisobutylaluminium hydride (DIBAH) is commonly used for the preparation of aldehydes from both aromatic and aliphatic nitriles,although the reagent provides moderate yields (48-90%).It has been also reported that other several reducing agents such as potassium 9-sec-amyl-9-borata-cyclo[3.3.1]nonane (K-9-sec-Am-9-BBNH),lithium tris-(dihexylamino)aluminium hydride (LTDHA) and lithium N,N'-dimethylethylenediaminoaluminium hydride (LDME-DAH) reduce chemoselectively nitriles to aldehydes.We have recently reported that diisobutylpiperidinohydro-aluminate (LDBPA,1) can effectively reduce esters to aldehydes in moderate to good yields at 0 deg C.