Scheme 1. Synthetic procedures to various monolignols and hydroxycinnamaldehydes. DDQ, 2,3-dichloro-5,6-dicyanobenzoquinone; LAH, lithium aluminium hydride; TBAF, tetrabutylammonium fluoride; TBSCl, tert-butyldimethylsilyl chloride; THF, tetrahydrofuran.