Date of Award

8-1-1971

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

Abstract

The recent reports of intramolecular Aldol, Dieckman and alkyla- 16 21 tion reactions of diazomethyl ketones by Burkoth and Woolsey have demonstrated that under proper conditions diazomethyl ketones will undergo normal base-catalyzed reactions. Similar intermolecular condensation reactions of diazomethyl ketones, however, have apparently not been in-, vestigated .

The purpose of the present work was to investigate the possibility of intermolecular base-catalyzed alkylation and aldol-type condensations of diazomethyl ketones of the type RCH^COCHN^ . The reactions of the hydroxydiazo ketone adducts resulting from aldol condensation and which are generally not available, would also be of interest.

The initial work with l-diazo-2-butanone (3 5) and benzaldehyde revealed that condensation took place preferentially at the diazo carbon to give 2-diazo- 1-hydroxy-l-phenyl-3-pentanone (4 1) as a viscous liquid. However, further work on this compound was abandoned in favor of l-diazo-3-phenyl-2-propanone (36).

When diazo ketone 3_6 was treated with benzaldehyde, the condensation once again occurred at the diazo carbon and resulted in the formation of 3-diazo-l,4-diphenyl-4-hydroxy-2-butanone (42).

Irradiation of the hydroxydiazo ketone 42_ in benzene or methanol below 50° gave 1,4-diphenyl-1,3-butanedione (43) . The dione 43 was also the only product isolated from the pyrolysis of 42. in refluxing chlorobenzene

Treatment of the hydroxydiazo ketone 42. with hydrogen chloride gas gave 20% of the dione 43. and 31% of 3-chloro-l, 4-diphenyl-4- hydroxy-2-butanone (44). Similarly when treated with hydrogen bromide gas, 42. gave 10% of the dione 43. and 45% of 3-bromo-l, 4-diphenyl-4- hydroxy-2-butanone (45). The structures of 44. and 45. rests on the physical data and the reduction of 45. to 2-bromo-1,4-diphenyl-1,3-butanediol (49). The nmr spectrum of the diol 4jl unequivocally determined the point of attachment of the halogen.

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