TY - JOUR
T1 - Addition reactions of conjugated double bonds. Part II. The occurrence of 1,4- or 1,2-addition in the reduction of some aryl αβ-unsaturated ketones with metal hydrides
AU - Iqbal, K.
AU - Jackson, W. R.
PY - 1968/1/1
Y1 - 1968/1/1
N2 - Some substituted trans-chalcones, crotonophenone, benzylideneacetone, and 3-phenylcyclohex-2-enone have been reduced with sodium borohydride in three solvents. In diglyme and propan-2-ol the proportion of attack at the β-carbon atom (1,4-addition) is less in the last two compounds than in the others. Reduction of the chalcones or crotonophenone in pyridine led to almost exclusive double-bond saturation. The related allylic alcohols are also reduced under these conditions. The ease of borohydride reduction of allylic alcohols appears to be connected with the ease of the base-catalysed allylic alcohol-saturated ketone rearrangements, though the allylic alcohols are stable to rearrangement in pyridine solution. An explanation is suggested.
AB - Some substituted trans-chalcones, crotonophenone, benzylideneacetone, and 3-phenylcyclohex-2-enone have been reduced with sodium borohydride in three solvents. In diglyme and propan-2-ol the proportion of attack at the β-carbon atom (1,4-addition) is less in the last two compounds than in the others. Reduction of the chalcones or crotonophenone in pyridine led to almost exclusive double-bond saturation. The related allylic alcohols are also reduced under these conditions. The ease of borohydride reduction of allylic alcohols appears to be connected with the ease of the base-catalysed allylic alcohol-saturated ketone rearrangements, though the allylic alcohols are stable to rearrangement in pyridine solution. An explanation is suggested.
UR - http://www.scopus.com/inward/record.url?scp=37049136273&partnerID=8YFLogxK
U2 - 10.1039/J39680000616
DO - 10.1039/J39680000616
M3 - Article
AN - SCOPUS:37049136273
SN - 0022-4952
SP - 616
EP - 620
JO - Journal of the Chemical Society C: Organic Chemistry
JF - Journal of the Chemical Society C: Organic Chemistry
ER -