Dihydrosinapyl alcohol

The ether-soluble fraction from hydrol lignin A was analyzed by NMR spectra and by gas chromatography. The NMR spectra is nearly identical with that of dihydroconiferyl alcohol and dihydrosinapyl alcohol, which were shown to be present in large amounts by gas chromatography. 

A significant observation was reported (6) in 1958. From the products of the alkaline hydrogenation of maplewood, Arlt et al. isolated two new products, dihydrosinapyl alcohol and 4-(2-hydroxyethyl)syringol, along with previously reported phenolics. 

The similar spectrum of products isolated under similar conditions of reaction from hard and softwoods indicates a basic similarity in the structural features of the releasable fragment of each species. The liberation, as the major product, of either dihydroconiferyl alcohol or dihydro-coniferyl alcohol plus dihydrosinapyl alcohol (depending on the wood species) indicates that a fairly accessible portion of the lignin substance is of a polyphenylpropanoid structure. The other, more highly fragmented products are most likely secondary reaction products derived from the initially liberated phenylpropanoid compounds. As such they should not be considered as unique units of lignin structure. 

Hydrogenolysis has also found use in a lignin biosynthesis study in which 14C-labeled lignin precursors were administered to wheat plants and maple twigs and ultimately recovered in the form of the typical lignin hydrogenolysis products, dihydroconiferyl and dihydrosinapyl alcohols (Brown and Neish 1959). 

---