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Please login to access the full content or check if you have access via Variation 6: From 2-Alkoxy- and 2-(Dimethylamino)-1,3-dioxolanes

DOI: 10.1055/sos-SD-047-00322

Kostikov, R. R.; Khlebnikov, A. F.; Sokolov, V. V.Science of Synthesis, (201047851.

An alternative one-pot procedure for the synthesis of alkenes from vic-diols is known as the Eastwood deoxygenation,[‌328‌] which like the CoreyWinter reaction depends upon the fragmentation of a 1,3-dioxolane intermediate. According to this protocol, a diol is treated with a trialkyl orthoformate at high temperature (140180°C), followed by thermolysis of the resulting 2-alkoxy-1,3-dioxolane 151 (160220°C) in the presence of a carboxylic acid (typically acetic acid). A related procedure is the conversion of vic-diols with (dimethylamino)dimethoxymethane into 2-(dimethylamino)-1,3-dioxolanes, which are then either quaternized in situ with iodomethane or heated under reflux in acetic anhydride, which in both cases leads to fragmentation to afford an alkene (see also HoubenWeyl, Vol. 5/1b, p 748) (Scheme 55).[‌203‌,‌244‌,‌245‌]

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Me8MMM(MMe)8, MeM, MM8Me8, ee, eeee Me8M, eeee 88 [‌888‌]
MM(MMe)8, MMMM, MMM, 8e, eeee Me8M, 888°M, eeeeee eeee, 8.8e 88e [‌888‌]
MM(MMe)8, MMMM, MMM, eeee Me8M, 888°M, eeeeee eeee, 8e 88e [‌888‌]
MM(MMe)8, MMMM, MMM, eeee Me8M, 888°M, eeeeee eeee, 8.8e 88e [‌888‌]
MM(MMe)8, MMMM, MMM, 8e, eeee Me8M, eeee, 8e 88 [‌888‌]
Me8MMM(MMM8e-Me)8, eeeeeee, eeee, 88e, eeee Me8M, eeee, 88e 88 [‌888‌]
MM(MMe)8, MeMM, 888°M, 8e, eeee 888°M, 8e 88 [‌888‌]

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(M)-Δ8-Meeeeeeeeeeeeee (888); Meeeeee Meeeeeeee:[‌888‌]

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(M)-8,8-Me-8-eeeeeeeeeeeeeee (888); Meeeeee Meeeeeeee:[‌888‌]

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