The photoinduced pinacolisation of 4-oxo-4-phenylbutanamides 1 afforded 4,5-dihydroxy-4,5-diphenyloctanediamides 2 and 3 with unusual diastereoselectivities up to 83%, which depends on the amide substituent. In this reaction the solvent diethyl ether acts as a hydrogen donor. The structures of pinacols 2 and 3 were confirmed by X-ray analyses. Possible reasons for the diastereoselectivity and the preferred