52. Preparation of αζ-diphenylhexatriene and 1 : 4-diphenylbenzene from cinnamaldehyde

An Unusual Oxidation of a Benzylic Methylene Group by Thionyl Chloride: A Synthesis of 1,3-Dihydro-2-[2-(dimethylamino)ethyl]-1,3-dioxopyrrolo[3,4-c]acridine Derivatives

“…Although thionyl chloride is routinely used as a chlorinating agent, “atypical” reactions have been reported. Some examples are the reactions of compounds with an active methylene group involving O-sulfinylation which produced gem dichlorides via addition reactions at a carbonyl group − or C-sulfinylation via the Hell−Volhard−Zelinsky reaction to give sulfinyl chlorides which may further undergo a Pummerer-type rearrangement and give various products, including α-chlorosulfenyl chlorides, sulfines, and thiones. − These compounds can be converted to ketones through acidic hydrolysis. − However, as far as we can determine, the direct oxidation of a methylene to a carbonyl group by thionyl chloride has not been reported. We report herein several cases of the unexpected direct oxidation of such a benzylic methylene in two fused-acridine systems by thionyl chloride.…”

The Synthesis of Substituted Terphenyls

“…For instance, 4,4"-dimethoxy-p-terphenyl has been isolated in 0.1 per cent yield from the reaction of anisylmagnesium bromide with 2-chlorocyclopentanone (102). p-Terphenyl can be obtained from cinnamaldehyde by successive treatment with thionyl chloride and sodium iodide (124), or by treatment with a zinc-copper couple and distillation (93), as well as by passing benzene over heated potassium (1). Some o-terphenyl was found amongst the pyrolysis products of cinnamylidenemalonic acid, C6H6CH=CHCH=C(COOH)2 (13, 56, 57).…”