Sowden-Fischer synthesis

Digressing from reductive desulfurization into stereochemistry, we may use this experimental proof of the equivalent symmetry of D-mannitol as a basis for an independent proof of the configurations of D-mannitol and D-arabitol. The reduction of D-arabinose yields the optically active pentitol, D-arabitol application of the Sowden-Fischer synthesis to D-arabinose yields D-mannose86 which upon reduction gives D-mannitol. 

This second approach70 was based on the nitromethane synthesis,71 and involved, as the key intermediate, l-C-nitro-l-hexene-D-n6o-3,4,5,6-tetrol tetraacetate (66), previously reported by Sowden and Fischer.77 In re-studying their conversion of D-ribose (64) into the hexenetetrol (66), it was possible70 to secure 2,3,4,5,6-penta-O-acetyl-l-deoxy-l-nitro-D- altritol (65) as crystalline material. When (65) was subjected to the Schmidt-... 

The Nef reaction has been employed for over fifty years in carbohydrate synthesis. A two-step process referred to as the Snowden method has been widely used to effect the chain elongation of sugars via the nucleophilic addition of the nitromethane anion to an aldehyde group followed by Nef reaction to provide a new aldehyde.6 For example, in early studies Sowden and Fischer described the conversion of 35 to 36 through addition... 

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