Dulcitol 1,6-dibenzoyl

The nature of the condensation product derived from any given pair of reactants is frequently independent of the type of catalyst used, but this is not always the case. Haskins, Hann and Hudson, for example, demonstrated that at room temperature hydrogen chloride catalyzes the formation of a 2,3,4,5-dibenzylidene derivative of 1,6-dibenzoyl-dulcitol,... 

Tanasescu and his co-workers88-70 have shown that o-nitrobenzylidene acetals, in chloroform or benzene solution, undergo photochemical transformations when exposed to sunlight. It appears that, under these conditions, an o-nitrobenzylidene derivative (III) may be converted into an isomeric o-nitrosobenzoy lester (IV). Thus, Tanasescu and Macov-ski86 showed that a di-(o-nitrobenzylidene)-dibenzoyl-dulcitol, later shown to be 1,3 4,6-di-(o-nitrobenzylidene)-2,5-dibenzoyl-dulcitol,48 could... 

The benzylidenation of 1,6-dibenzoyl-dulcitol gives rise to one of two products, depending upon the conditions of the reaction. The use of gaseous hydrogen chloride at room temperature for 12 hours, or of zinc chloride at 60° for 24 hours, results in the formation of a dibenzoyl-dibenzylidene-dulcitol, which melts at 119-120° and which, when treated with sodium methoxide, gives a dibenzylidene-dulcitol melting at 149-1500.1 On the other hand, when the condensation is catalyzed by zinc chloride at room temperature, the main product is an isomeric dibenzoyl-dibenzylidene-dulcitol, which melts at 147-148° and which can be saponified to a dibenzylidene-dulcitol melting at 173-174°. The unstable dibenzoyl-dibenzylidene-dulcitol (m. p. 147-148°) is converted into its stable isomer (m. p. 119-120°) by treatment with zinc chloride and benzaldehyde at 60°, Four independent lines of evidence reveal that,... 

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