Lignin hydrogenation, dimers from

The Structure of Dimers from the Alkaline Hydrogenation of Lignin... 

A third dimer was obtained from Norway sprucewood in somewhat impure condition (m.p., 117°-127°C.). However, its vapor phase retention time and ultraviolet spectrum 23) were identical with those of authentic 5,5 -diethyl-2,2 -dihydroxy-3,3 -dimethoxybiphenyl (VII), m.p. = 143°C. (P). Furthermore, the NMR spectrum and melting point of its purified diacetate were identical with those of the synthetic compound. The corresponding 5,5 -di-w-propyl derivative has already been isolated from neutral hydrogenation of softwood lignin in our laboratory 18). 

In summary, we have isolated and identified two dimeric compounds from the alkaline hydrogenation of sugar maplewood lignin—namely, 1,2-(4,4 -dihydroxy-3,3, 5,5 -tetramethoxydiphenyl)-ethane (I) l,2-(4,4 -... 

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