Organic Lab Reactions 198

Organic Lab Reactions 198 - and LXII and ethers derived...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
REDUCTION OF a-BROMOKETONES CH 2 COCH 2 OCOCH 8 CH 2 CHOHCH 4 OH 193 !—OCH 2 C 6 H 5 OCH 8 CH 2 C 6 H B OCH 8 Lii Lin Reduction of a-Bromoketones Reduction of <x-bromoacetophenone gave the corresponding bromo- hydrin in 85% yield. 6 Smooth reduction also occurred with chloral 2> l6 and bromal. 6 However, a-bromopropiophenone **• ** gave only 35 to 42% yields of the bromohydrin; the remainder of the product was halogen-free, consisting of a mixture of benzylmethylcarbinol andsome ethers. From a-bromoisobutyropKenone (LIV) **• 45 very little bromohydrin (LV) was obtained with aluminum isopropoxide in boiling isopropyl alcohol. The main material was a mixture of the carbinols LX, LXI,
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: and LXII and ethers derived from them. The occurrence of these products was explained by the fonnation of the oxide (LVI) from the intermediate bromohydrin. The oxide is capable of rearrangement, with or without the migration of a methyl or phenyl group, to give the car-bonyl compounds LVTI, LVIII, and LIX which would give rise to the. carbinols through further reduction. GH, , * &lt;0-CH-c/ -OH Br CH, LV CH, HOCH &quot; Stevens, J. Am. Chm. Sot., 60, 3089 (1938). 44 Stevens, Allenby, and DuBois, J. Am. Chetn. Soc., 62, 1424 (194g). 46 Stevens and Aflenby, / . Am. Chem. Soc., 68, 3264 (1940)....
View Full Document

Ask a homework question - tutors are online