0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login or sign up for a free trial to access the full content. Method 4: Reactions of Aryl and Alkyl Acetylenes in Stoichiometric Metal-Mediated Pyrrole Syntheses

DOI: 10.1055/sos-SD-109-00312

Lubell, W. D.; St-Cyr, D. J.; Dufour-Gallant, J.; Hopewell, R.; Boutard, N.; Kassem, T.; Dörr, A.; Zelli, R.Science of Synthesis Knowledge Updates, (20131184.

To expand the scope beyond electron-poor acetylenes in the [3 + 2]-cycloaddition approaches described in the previous section, stoichiometric metalation of the acetylene component can be used to enhance reactivity. For example, lithium acetylides are sequentially reacted with tungsten (or molybdenum) carbenes and imines to furnish 1-(phenylsulfonyl)pyrroles such as 55 (Scheme 35).[‌78‌,‌79‌]

Meeeee 88 Meeeeee Meeeeeeee ee Meeeeeee ee e Meeeeee Meeeeee, e Meeeeeee Meeeeeeee, eee ee Meeeeeeeeeeee Meeee[‌88‌]

Meeee-eeeeeeeee eeeeeee eeeeeeeee eeee eeee eeee eeeeeeee eeee ee eeeeeeeee eeee 8 eeeeeeeeeee ee ee α-eeeeeeeeeeeee (Meeee 8, eeeeeee 8 eee 8) ee eeee eee eeeeeeeee α-eeeeeeeeeeeeee (Meeee 8, eeeeeee 8–8).[‌88‌] Mee eeeeeeee ee eeeeeeee eeeeeee ee eeeeeee ee eee eee ee eeeeeeeeeeeeee eeeeeeee(MM), eeeeeeee eeee eeeeeeee(MM) eeeeeeeeeeee eee eeeeeeeeeeeeeeeeee eeeeeeee (−88 ee −88 °M, 8.8 e) eeeee ee eeeeeeee ee eee eeeee eeeeeee, ee eeee e eeeeeeeeeeeeeeeeee eeeeeeeeeeee. Meeeeeee 88 eee eeeeeeeeeeeeeeee eeeeeeeeeee eeee eeeeeee eeeeeee ee eeee eeeeeeeeeee (eeeeeee eeeeeee 8/8 eee 8 ee Meeee 8). Mee eeeeeeeee 8-eeeeeeeeeeee eeeee eeeeeee eeee eeeeeeeeeeeeeee eee eeeeeeeeee ee eee eeeeeeeeeeeee eeeeeee eeeeee eeeeee eeee eeeeeee. Meeeeeeee eee eeeeeeeeeee ee eee 8-eeeeeeeeeee eeeeeeeeeee, eeeeeeeeeeee, eeeeee 8-eeeeee- eee 8-eeeeeeeeeeeeeee.

Meeee 8 Meeeeeee ee Meeeeeeeeeeeeeeeeee Meeeeeeeeee eee Meeeeee ee eee Meeeeeeee ee 8-(Meeeeeeeeee)eeeeeee-8-eeeeeeeeeeeee[‌88‌]

Meeee M8 M8 M8 M8 Meeee (%) Mee
8 Me M Me Me 88e [‌88‌]
8 Me (MM8)8Me 8-MeM8M8 (MM8)8Me 88 [‌88‌]
8 Me (MM8)8Me 8-eeeee (MM8)8Me 88 [‌88‌]
8 Me (MM8)8Me Me (MM8)8MMMMMM 88e [‌88‌]
8 Me M (MM8)88 88 [‌88‌]

e (Meeeeeeee)eeeeeeeeeeee (8 eeeee) eee eeee eeeeeee ee eeeeeeeeeeeeeeeeeee.

e 88:88 eeeeeee eeee eeeeeeeeeee 88 [M8 = (MM8)8MMMMMM; M8 = Me].