Precocene Analogues, Deuteration A convenient route for the preparation of title compounds from benzopyran-4-one (1) and its corresponding 3,3-H2 deuterated analogue (2) is reported. Treatment of 1 or 2 with lithium aluminum deuteride followed by dehydration afforded, respectively, 4-H precocene (3c) or 3,4-H2 precocene (3b). Likewise, reduction of 2 with lithium aluminum hydride and subsequent...
