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by this reagent. Kishner-Wolff reduction of (+)-isopinocamphone (IIIa; R = =O) gave a poor yield of pinanes consisting of 87% (g.1.c.) of the trans-isomer.

Demethylhomopterocarpin (I; R = H) has been synthesised and shown to be identical with an extractive from Andira inermis.IN an earlier Paper,l extractives from the West Indian hardwood, Andira inermis (Wright) H. B. K. were described. One of these, m. p. 112-113", [a],20 -2229.5' , showed ultraviolet absorption characteristics similar to those of homopterocarpin (I; R = Me) anddemethylpterocarpin (11; R = H). We have now synthesised the racemic form of demethylhomopterocarpin (I; R = H) and shown it to be identical in gross structure with the extractive. Further, the naturally occurring isoflavonoid affords homopterocarpin (I; R = Me) on methylation.The synthetic product (I; R = H) had m. p. 194-195", some 80" higher than that of the optically active form, but its ultraviolet spectrum was in close agreement with that of the naturally occurring material (see Experimental section). The infrared spectra in chloroform of the two forms were identical, but in Nujol and potassium bromide, whilst being similar, were not identical. These are characteristics of a racemic compound and one of its active components. Racemic compounds usually have higher melting points than their components and in the solid state have different infrared spectra. In solution, racemic compounds dissociate and their spectra and those of their components become identical. The acetate of our synthetic demethylhomopterocarpin melted 45" lower than the acetate of the naturally occurring isoflavonoid but the two acetates showed identical ultraviolet and infrared spectra.The natural and synthetic phenols and acetates had identical RE' values and mixtures of them were inseparable by chromatography.Only one racemate of demethylhomopterocarpin is possible, since strain forbids transfusion at carbons 3 and 4. The naturally occurring isoflavonoid has the P-H configuration at these centres2The synthesis was carried out as follows. 2,4-Dimethoxybenzaldehyde was condensed with nitromethane in presence of methylamine hydrochloride and sodium ~a r b o n a t e , ~ giving the nitrostyrene (111; R = Me).5 This was reduced over palladised charcoal to. 2,4-dimethoxyphenylacetaldoxime (IV) ,6 which on dehydration gave 2,4-dimethoxybenzyl cyanide. Almost quantitative conversionThe synthetic acetate thus behaves as a racemic mixture.The overall yield of cyanide was about 20%.