Science of Synthesis

Schobert, R.; Hölzel, C.; Barnickel, B., Science of Synthesis, (2010) 47, 27.

Methylenetriphenylphosphorane (‌1‌) reacts with 2-(chloromethyl)oxirane (epichlorohydrin) in the presence of 1 equivalent of butyllithium to give [2-(oxiran-2-yl)ethylidene]triphenylphosphorane in equilibrium with an oxaphospholane betaine. The reaction of this species with paraformaldeyde affords (2-methylenecyclopropyl)methanol (‌45‌)[‌248‌,‌249‌] (‌Scheme 18‌). The analogous 4-methyl-6-methylene[1,3]dioxepanes[‌250‌] and 2-aryl-4-methylenetetrahydrofurans[‌251‌] are obtained similarly.

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[(8M)-8-Meeeeeeeeeeeeeeeeeee]eeeeeeee (‌88‌):[‌888‌]

M eeee ee (M)-(−)-eeeeeeeeeeeeeee (8.88 e, 88.8 eeee) ee MMM (88 eM) eee eeeee ee e eeee ee Me8M=MM8 ‌8‌ [eeeeeeee eeee eeeeeeeeeeeeeeeeeeeeeeeeee eeeeee (8.88 e, 88 eeee) eee 8.8 M MeMe ee eeeeee (8.8 eM, 88.8 eeee)] ee eeeeee ee −88°M. Meeee eeeeee eeee eeeeeee eee 8 e, eee eeeeeee eee eeeeee ee ee −88°M, eeeeeee eeee 8.8 M MeMe ee eeeeee (88.8 eM, 88 eeee), eee eeeeeee eee 8 e. Meeeeeeeeeeeeeee (8.8 e, 88 eeee) eee eeeee ee eeee eeee ee eee eeeeeee ee −88°M. Mee eeeeeee eee eeeeee ee ee ee eee eeeeee eeee M8M. Mee eeeeeeeee eeeeeeeeee eee eeeeeeeee eeee Me8M (8 × 88 eM) eee eeeee (MeMM8), eee eee eeeeeeee eeee eeeeeee eeeee eeeeeee eeeeeeee ee eeee e eeee eeeeee eee, eeeee eee eeeeeeee ee eeeeeeeeeeeeee (eeeeee eee, MM8Me8). Meee-ee-eeee Meeeeeeee eeeeeeeeeeee eeeeeeee eee eeeeeeeeeeeeeeee eeee eeeee eeeeeeee ‌88‌; eeeee: 8.88 e (88%); ee 888–888°M; [α]M88 −8.8 (e 8.88, MMMe8).

References

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• 8.Meeeee-Meee, (8888) M 8e, 888.