Science of Synthesis

Constantieux, T.; Rodriguez, J., Science of Synthesis, (2005) 26, 425.

The transformation of α,β-unsaturated ketones, via the fragmentation of their α,β-epoxy hydrazone derivatives, is a very useful procedure for the synthesis of alkynones. In pioneering works, tosylhydrazones were first used by Eschenmoser,[‌68‌–‌70‌] and later, ­independently, by Tanabe.[‌71‌,‌72‌] The fragmentation of these substrates gives four parts, a ketone, an alkyne, nitrogen, and 4-toluenesulfonic acid. If both the ketone and alkyne moieties are connected, this methodology allows efficient entry to acyclic or cyclic ­alkynones. The transformation may be viewed as outlined in ‌Scheme 21‌.

‌Meeeee 88‌ Meeeeee Meeeeee ee eee Meeeeeeeeee Meeeeeeeeeeee Meeeeeee

Mee eeeeeeeeeeeeee eeeeee eeeee eeee eee β-eeeeeeeeeee eeeeee ee eeeeeeee α,β-eeeee eeeeeee. Me eeeee eeeeeeee eeeeeee, eee eeeeeeee eeeee ee e eeeeee eeee eeeeeeeee, eeeee eee ee eeeeee ee e eeeeeee eeeee-eeeeee Meeeeeeeeee-eeee eeeeeeee (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeeee ee eee Meeeeeeeeee Meeeeeeeeeeee Meeeeeee

Mee eeeeeeeee eeeee ee eeee eeeeee ee eeeeeeeeeee ee eee eeeeee eeeeeeeee ee eeeeeeeeeee eeeeeee eeee eeeeeeeeeeeeeee, ee eeeeeeeeeee eee eeeeee eeeeeeeee eeeeeeee eeeeeeee. Meee ee eeeee eeeeeee, eeee ee eeeeeeee (‌88‌) eee eeeeeee (‌88‌), eeee eeeeeeeeee ee eee eeeeeeeee eeeeeeee (‌Meeeee 88‌).[‌88‌,‌88‌] Meee eeeeee eee eeee eeee eeeeeee ee eee eeeeeeeee ee eee eeeeeeeeee eeeeeee eeeeeeee-8-ee-8-eee (‌88‌) (‌Meeeee 88‌).[‌88‌] Mee Meeeeeeeeee eeeeeeeeeeeee eee eeee eeeeeeee ee eee eeeeeeeee ee eeeeeee β,γ-eeeeeeeeee eeeeeeee,[‌88‌,‌88‌] eeee ee 8,88-eeeeeeee-8-eee-8,88,88-eeeeee (‌88‌) eeeee ee eeeeeeeeeee eeee 8-eee-8,88-eeeeeeeeeeee-8,8-eeee eeeeeeeee (‌88‌) (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeee ee Meeeeeeee Meeeeeeeeee eee eee Meeeeeeeeee Meeeeeeeeeeee Meeeeeee[‌88‌,‌88‌,‌88‌]

Me eeeeeeeeee eee eeeeee eeeeeeeeeeeeeee eeeeeeeee[‌88‌] ee eeee eeee- eee eee-eeeeeeeeee (‌88‌), e eee eeeeeeeeee eeeeeeeee, eeee ee eeeeeee eeeeeeee ‌88‌ ee ee eeeeeeeeeeee, eeeeee eeeeeeeeee eeee eee eeeeeeeeeeeee ee eee eeeeeeeeeeeeee eeeeeeeeee ee 8-eeeee-8-eeeeee-8-eeeeeeeeee[8.8.8]eeeeee-8-eee (‌88‌) (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeeee ee eee-Meeeeeeeee[‌88‌]

Meeeeeeeeeee, eee eeeeeeeeeeeeee eeeeee eeee eee eeee eeee eeeeee eee eee eeeeeeeeeeeee eeeeeeee eeee eee eeeeeeeeee eee eeee β-eeeeeeeeeeeee eee eeeeeee α,β-eeeee ­eeeeeee. Me eeeeeeee eeeee eeeeeeee, eeee eeeeeeeeeee eeeeeeeeee eee eeeeeeeeeeee eeee eeee eeeeeeeeee ee eeeee eeeeee,[‌88‌] eeeeeeeeee,[‌88‌] M-eeeeeeeeeeeeeee,[‌88‌] 8,8-eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee,[‌88‌] 8,8,8-eeeeeeeeeeeeee eeeeeeeeeee,[‌88‌] eee eeeeeeeeee-8-eeeeeeeeeeeeeeeeee.[‌88‌] Me eeee ee eeeee eeeee, eee eeeeeeee eeeeeeee eeeeeeee eeeeeee e ee­eeeeeeeee eeeeeeeeeeee ‌88‌, ee eeeee ee ‌Meeeee 88‌.

‌Meeeee 88‌ Meeeeeeeeeeee Meeeeee eeeeeee e Meeeeeeeeee Meeeeeeeeeee

Mee eeeeeeeee ee eeeee eeeeeee eeee eeeeeeeeee eeeeeee eeeeee eee eeee ee eeeeeeeee. Meeeeee, ee eeeeeeeeeeeeeeeeeeeeee eeeeeeeeeeeee ee eeee eeeeeeeee, eeee eeeeeeee eee eeeeeeeeeee eeee, eee eeee eeeeeeeee.[‌88‌] Me eeeeeeeeeee ee ‌Meeeee 88‌, eeeeeeeee ee eee eeeeee eeeeeeee ‌88‌, eeeeeeeee ee eeeeeeee (‌88‌, ‌Meeeee 88‌), eeeeee ee eeeeeeeee ee eee eeeeeeee eeeeeeeee ‌88‌ eeee ee eeeeee ee M-eeeeeeeeeeeeeeee ee eeeeeeee.

‌Meeeee 88‌ Meeeeeeeeeeee ee ee Meeeeeeeeeeee Meeeeeeee eeee Meeeeeeee eeee ee Meeeeeeeeeee eeeee Meeee Meeeeeeeee[‌88‌]

Meeeeeeeeeee Meeeeeeeee

Mee-8-ee-8-eee (‌88‌); Meeeeee Meeeeeeee:[‌88‌]

Me e eeeeeeeeeeee eeeeeee eeee ee 8-eeeee-8-eeeeee-8-eeeeeeeeee[8.8.8]eeeeee-8-eee (‌88‌; 88.8 e, 888 eeee) ee MM8Me8 (888 eM) eee MeMM (88 eM) ee 8–8°M eee eeeee eeeeeeeeeeeeee (8.8 e, 88.8 eeee) ee eee eeeeeee. Meeeeeee eee eeeeeeeee ee 8–8°M eee 8 e, eeeeeeee ee 8 e ee ee. Mee eeeeeee eee eeeeee eeee M8M (888 eM) eee eeeeeeeee eeee eeeeee (8 × 888 eM). Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeee M8M (8 × 888 eM) eeeeeeee ee eee. MeMMM8 (8 × 88 eM). Meeee eeeeee (MeMM8) eee eeeeeeeeeeeee ee eeeee, eee eeeeeeeee eee eee eeeeeeeee ee eeeeee e eeeeeeeee eee; eeeee: 88.8 e (88%); ee 88°M/8.8 Meee.

Meeeeeeeeeeeeee-8-ee-8-eee (‌88‌); Meeeeee Meeeeeeee:[‌88‌]

MMM (8.8 e, 88.8 eeee) eee eeeee, ee eee eeeeeee, ee e eeeeeee eeeeeeeeee ee eeeeeeeeeeeeee ‌88‌ (8.8 e, 88.8 eeee) ee eee eeeeeee (88 eM) eee e-MeMM (88 eM) ee −88°M. M eeeeeeee eee eeeeeeeee eee eeeeeeee eee eee eeeeeeeeeee ee eee eeeeeeeee eee eeee eeee ee –8°M. Meeee 8 eee ee 8.88 M MeMMM8 (88 eM) eee eeeee, eeeeeeee ee M8M (88 eM). Mee eeeeeee eee eeeeee ee 88°M eee 88 eee eeeee ee eee eeeeeeee ee eeeeeeeee eeeee (888 eM) eee 88% ee MeMM (888 eM). Meeeeeeeee eeee eeeeeeeee eeeee, eeeeee, eee eeeeeeeeeeee eeee eee 88% eeee, eeeeeeeeeee eeeee; eeeee: 8.88 e (88%).

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 8/8e, 8888.