Three minor products from the irradiation of acetophenone in ether are described, and the mechanism of their formation is discussed.Canadian Journal of Chemistry, 47, 687 (1969) Irradiations of aromatic ketones in hydrogendonating solvents have long been known to give mixtures of reduction products, predominantly pinacols (I), and recent publications concerning the mechanism of the photoreduction of benzophenone to benzopinacol (2-5) have prompted this report. During the course of other investigations it was found that irradiation of acetophenone in ether/cyclohexane solvent gave, as expected, the acetophenone pinacols in good yield (6). The product mixture also contained three minor constituents which were separated chromatographically and identified.Two butan-2-01 derivatives were isolated in 6% yield each and the gross structure 1, for both of them, was assigned from their spectra. The infrared (i.r.) spectra of each showed a monosubstituted phenyl, a hydroxyl group (probably tertiary) and no carbonyl, and differed only in details of the "fingerprint region". The proton magnetic resonance (p.m.r.) spectra, however, differed appreciably. Both showed the presence of one singlet, one doublet, and one triplet methyl group, but in one case (compound la) the doublet and triplet were well-separated, and in the other (compound lb) almost superimposed. Three protons on carbon adjacent to oxygen appeared as complex multiplets in each, the patterns differing in detail. These were consistent with the A, B, and A' portion of an ABX, pattern superimposed on an A'X', (7,8). Five aromatic protons and one hydroxyl were present in each compound. The compounds l a and 16 were evidently diastereoisomeric and on the basis of the relative chemical shifts of the methyl groups, and the anticipated preferred conformations (9), the structures were tentatively proposed as shown.The third minor product, 2 (3% yield after Ultraviolet (u.v.) and i.r. spectra showed that the purification), was also identified by its spectra. compound was a substituted aromatic ketone, and all the non-equivalent protons were clearly lPresent address: Chemistry Department, University resolved in the p.m.r. spectrum. The p-substi-
