Date of Award
Master of Science (MS)
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.
Khalil, Mohammed H., "3-Diazo-1,4-Diphenyl-4-Hydroxy-2-Butanone: Preparation and Reactions" (1971). Theses and Dissertations. 3496.