Science of Synthesis

Hay, M. B.; Hicks, J. D., Science of Synthesis: Cross Coupling and Heck-Type Reactions, (2013) 2, 130.

The palladium-catalyzed amination of alkenyl halides by primary aromatic amines is an efficient alternative to classical condensation methods for the construction of N-arylimines ‌40‌, especially when the condensation reaction involves a volatile carbonyl substrate.[‌78‌] A significant limitation of this method is the narrow scope of alkenyl halide starting materials that have been used for this transformation, as most examples are 2-halopropenes or (1-halovinyl)benzenes. The amination of alkenyl bromides is typically carried out at elevated temperatures in toluene in the presence of a palladium catalyst containing a bidentate ligand, such as BINAP[‌79‌] or 1,1′-bis(diphenylphosphino)ferrocene,[‌78‌] and sodium tert-butoxide[‌79‌] or cesium carbonate[‌78‌] as the base (‌Scheme 26‌). Alkenyl chloride electrophiles require catalysts containing more electron-rich ligands such as dialkyl(biaryl)phosphines.[‌80‌] Interestingly, competition experiments have demonstrated that amine alkenylations proceed preferably to arylations when alkenyl and aryl bromides are present.[‌79‌] This is attributed to the faster oxidative addition rate of alkenyl bromides relative to aryl bromides.[‌79‌]

‌Meeeee 88‌ Meeeeeeee-Meeeeeeee Meeeeeeee ee Meeee Meeeeee[‌88‌-‌88‌]

‌Meeeeeeeeee 88‌

e Meeee (Me/eeeeee) 8:8.8.

e Meeee (Me/eeeeee) 8:8.

Meeeeee, eee eeeeee-eeeeeeeee eeeeeeeee ee eeeee eeeeeee ee eeeeeee eeeeeeee eeeeee eee eeee eeeeeeee eeeee e eeeeeeee eeeeeeeee ee eeeeee(M) eeeeee/M,M′-eeeeeeeeeeeeeeeeeeeeeee (MMMMM), eeeeeeee eeee eeeeeeee eeeeeeee eeee eeeeeeeeeeee eee eee eeeeeee eeeee (‌Meeeee 88‌).[‌88‌]

‌Meeeee 88‌ Meeeee-Meeeeeeee Meeeeeeee ee e Meeee Meeeee[‌88‌]

Meeeeeeeeeee Meeeeeeee

M-Meee Meeeee Meeeee Meeeee ‌88‌; Meeeeee Meeeeeeee:[‌88‌]

M Meeeeee eeeee eeeee M8 eee eeeeeee eeee MMMMM (8 eee%), Me8(eee)8 (8 eee%), e-MeMMe (8.8 eeeee), eee eeeeeee (8 eM/eeee eeeeeee eeeeeee). Meeee 8 eee, eee eeeeeee eeeeeee (8 eeeee) eee eee eeeeeeeee (8.8 eeeee) eeee eeeee eeeee M8 eee eee eeeee eee eeeeeeee ee ee eee eeee eee eeeeee ee 88 °M eeee eeeeeeee eeeee eee eeeeeeee eeeeeee eeeeeee eee eeee eeeeeeeeee eeeeeeee, ee eeeeee ee MM eeeeeeee. Mee eeeeeee eee eeeeeee ee eeee ee ee, eeeee ee ee eeeeeee, eee eeeeeeee eeeeeee Meeeee. Mee eeeeeeee eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeee eee eeeeeeeeeee ee eeeeeee eee eeeeeeee eeeee eeeeeee Meeeee, eee eee eeeeeeee eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeeeee eee eeeeee eeeee. Mee eeeeeee ‌88‌ eeeee ee eeeeeeee ee Meeeeeeee eeeeeeeeeeee eeeee eeee eeeeee (eeeeeeeee ee eee eeeeeee eeeee).

References