Organic Lab Reactions 196

Organic Lab Reactions 196 - very slow requiring two days...

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

View Full Document Right Arrow Icon
REDUCTION OF KETO ESTERS 191 Further Reduction to a Hydrocarbon. In the reduction of benzo- phenone with aluminum ethoxide the formation of 7% of diphenyl- methane was observed. When benzohydrol was treated with aluminum ethoxide under the same conditions, 28% reduction to diphenylmethane occurred. 12 In these reactions acetic acid, rather than acetaldehyde,'Was formed from the ethoxide. Aluminum isopropoxide does not give this type of undesirable reaction; with this reagent, pure benzohydrol is easily obtained in 100% yield from benzophenone. 6 - 37 However, one case "of reduction of a ketone to the hydrocarbon has been observed with aluminum isopropoxide. 17 When 9, 9-dimethylanthrone-10 (XLI) was reduced in xylene solution, rather than in isopropyl alcohol, to avoid formation of the ether (see p. 190), the hydrocarbon XLIII was formed in 65% yield. The reduction in either xylene or isopropyl alcohol was
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: very slow, requiring two days for completion. CH3 CH3 XLIII Reduction of Keto Esters Since aluminum alkoxides function effectively as catalysts for alcohol exchange in esters, 38 ' 89 reduction of keto esters by aluminum iso-propoxide frequently yields the isopropyl ester of the hydroxy acid. Thus the reduction of the cyclopropane derivative XLIV gave the iso-propyl ester of the reduced acid (XLV). 40 Similarly the substituted methyl /3-keto ester (XLVI) 41 gave upon reduction the isopropyl esters of the stereoisomeric reduced acids (XLVII). CsH 6-C=O - C<jH 5 — CHOH- CH C CeH 6- CH C COOCH3 COOCH(CHj,)s> XLIV XLV 87 Wilds, unpublished observations. 88 Fehlandt and Adkins, J. Am. Chem. Soe., 67, 193 (1935). •• Baker, J. Am. Chem. Soc, 60, 2673 (1938). 40 Schenk, J. prakt. Chem., [2] 134, 215 (1932). 41 Baohmann and Wilds, unpublished observations....
View Full Document

This note was uploaded on 11/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.

Ask a homework question - tutors are online