Ketones from 1,3-Dithiane Cyclobutanone

I he product is distilled through a spinning-hand column. The I raction hoiling at 95-100° is collected. The yield of cyclohut-anone is 12-15.8 g. (60-81%) (Note 14). 

If available, argon is preferable to nitrogen because of its higher density. 

The checkers used reagent-grade tetrahydrofuran (available from Fisher Scientific Company) from a freshly opened l)ottle. The submitters used tetrahydrofuran purified by distillation from lithium aluminum hydride. See Org. Syn., 46, 105 (1966), for warning regarding purification of tetrahydrofuran. 

During the entire reaction sequence a positive pressure of iq)proximately 50 mm. of nitrogen is maintained against the a( mosphere with a mercury bubbler. 

The titer of the solution should be determined prior to use. file checkers used product available from Foote Mineral Com-pany. 

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