3.3- Dimelhyl-2-butanone

An extension of the above preparative method of chirality transfer is the preparation of dioxolanes 16 from lactic acid and 3,3-dimelhyl-2-butanone (pinacolone)80. In this case the crude cis/trans ratio is already 95 5, thus, it is much better than the observed 80 20 ratio observed with trimethylacetaldehyde. Alkylation of 16 with benzyl bromide seems to proceed with a satisfactory 95 5 selectivity. 

Beiistein Handbook Reference) BRN 1752918 2-Butanone, 1,1-dichloro-3,3-dimethyi- 1,1-Dichlono-3,3-dimelhyl-2-butanone 1,1-Dichloro-3,3-dimethylbutan-2-one Dichloromethyl tert-butyl ketone Dichloropinacolin Dichloropinakolin ra.m-Dichlorpinakolin EINECS 245-111-7. 

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