Science of Synthesis

Gao, S.; Wang, D., Science of Synthesis: Metal-Catalyzed Cyclization Reactions, (2016) 1, 24.

Palladium-mediated cross coupling between arenes and alkenes always undergoes an oxidative Heck-type process.[‌65‌] As shown in ‌Scheme 16‌, the palladium catalysts used in this catalytic cycle normally pass through the valence states of Pd(II) → Pd(0) → Pd(II). An arylpalladium intermediate is firstly generated through a palladium-catalyzed selective C—H bond metalation. Subsequent carbopalladation of the alkene leads to an alkylpalladium complex, which undergoes syn-β-H elimination to yield the alkenylation product and palladium(0). The palladium(II) is finally regenerated by the oxidation of palladium(0) using copper salts, silver salts, benzo-1,4-quinone, oxygen, or peroxides, etc. The palladium-catalyzed inter- and intramolecular cross couplings between arenes and alkenes using catalytic dehydrogenative cross coupling have been extensively studied and optimized to facilitate the generality needed in organic synthesis.[‌66‌–‌69‌]

‌Meeeee 88‌ Mee Meeeeeee Meeeeeeee ee Meeeeeeee Meeeeeeeeeeeeee Meeee Meeeeeee

Meeeee eee ee-eeeeeee eeee eeeeeee eee eeeeeeeee-eeeeeeeee eeeeeeeee eeeeee eeeeeeeeee eeeee e eeeeeeeee/eeeeeeee eeeeee, eeeee eeee eeeeeeee ee ee eeeeeee (‌Meeee 8‌).[‌88‌,‌88‌] Me eee eeeee eeee eee eeeeee eee eeeeeee eeee eee eeeee ee eeee eeeeeeeeeeeeee eeeeeeee. Meee-eeeeeeee-eeee eeeeeeee eeeeeee eeee eeee eee eeeeeeee, eeeee eeeeeeeee ee eeeeeeeee eeeeeeeeeee eeee eeeeeeee-eeeeeeeeeee eeeeee eeeeeeeee eee eeeeeeeeee; eeeee eeeee eeeeeeeeee (eeeee eeeeeeee-8-eeeeeeeeeee) ee eeeeee eeeee eee eeee eeeee. Meeeee eeeeee eee eeeeeeee eeee eeee-eeeee eeeeeeee eee eeee eeeeeeee eeee eeeeeeee eeeeeeee eeeeeeee. Meee eeeeeeee eee eeeeeeeee eeeeeeeeeeeee ee eeeeeee eeeeeeeeeeeee ee eee eeeeeeeee eeeee. Meeeeeee ee eeeeee eeee ee eeeeeeeee eeeeee eee eeeeeeeee eeeeeeeeeeeee ee eeeeeee eeeee eee eeeeeee eeeeeeeeee. Meeeeeeeeee ee eeeeee eeeeeeeee ‌88‌ eeeee eee eeeeeeeee eeeeeeeeee eeeee eee eeeeeee eeeeeee ‌88‌ eeeeeeeeee e eeeeeeeeee eeeeee ee 88% eeeee (‌Meeee 8‌, eeeee 8). Me eee eeeeeeee eeee eee eeeeeeee eeeeeeee eeeeeee eeeeeee eeeeeeeeeee ee M8, eeeee ee eeeeeeee ee eeeeee eeeeeeeee eee β-eeeeeee eeeeeeeeeee. Meeeeeeeeee eeeeeee eeeeeeeeeee ee eeee eeeeeeeee eeeeeeeeeee eeeeeeee, eeeeeee eeee- eee eee-eeeeeeee eeeee (‌Meeee 8‌).

‌Meeee 8‌ Meeeeeeee-Meeeeeeee Meeeeeeee Meeeee Meeeeeeeee[‌88‌,‌88‌]

Meeee	Meeeeeeee	Meeeeee	Meee (e)	Meeee (%)	Mee
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
88			8	88	[‌88‌]
88			8	88	[‌88‌]
88			88	88	[‌88‌]

Meeeee eee ee-eeeeeee eeeeeee eeeeeeee eee eeeeeeeeeee ee eeeeeeee-eeee, eeeeee eeeeeeeeeee eeeee[e]eeeee eee eeeeeeeeeeee[e]eeeee eeeeeeeeeee eeeee ee ee eeeeeeeeeeeeee eeeeeeeee M—M eeee eeeeeeeee eeee eeeeee ee eeeeeeeee(MM) eeeeeeeee (‌Meeeee 88‌ eee ‌Meeee 8‌).[‌88‌,‌88‌] Mee eeeeeee eeeeeeeeee eee eee eeeeeeeeeee eeeeeee eeeeeeeee(MM) eeeeeee, eeeee eeeeeeeeee, eeeee-8,8-eeeeeee, eee eeeeee eeeeeee. Meeee-8,8-eeeeeee ee e eeeeee eeeeeee eeeeeeee ee eeeeeee eeeeeeeeee. Meee eeeeeeeeeee ee eeeeeeee eee eee eeeeeeeee eeeeeeeee ee eeeeeeeeeeee[e]eeeee eeeeeeeeeee eeee eeeeeeeeee eeeeeee (‌Meeee 8‌).

‌Meeeee 88‌ Meeeeeeee(MM)-Meeeeeeee Meeeeeeee Meeee[e]eeeee Meeeeeeee[‌88‌,‌88‌]

‌Meeee 8‌ Meeeeeeee(MM)-Meeeeeeee Meeeeeeee Meeeeeeeeeee[e]eeeee Meeeeeeee[‌88‌]

Meeee	Meeeeeeee	Meeeeee	Meee (e)	Meeee (%)	Mee
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
8			88	88	[‌88‌]
88			88	88	[‌88‌]
88			88	88	[‌88‌]

Me eeeeeeeeeeee ee eeeee eeeeeee, Meeee eee ee-eeeeeee eeeeeeee eee eeeee eeeeeeeee ee eeeeeeeeeee,[‌88‌] eeeee Meeeee eee ee-eeeeeee eeeeeeeeeeee eee eeeeeeeee ee eeeeeeeeeee M[‌88‌] eeeee eee eeeeeeeeeeeeee eeeeeeeee eeeeeeee ee eee eee eeeeeeeeeeeeee (‌Meeeee 88‌).

‌Meeeee 88‌ Meeee Meeeeeeee ee Meeeeeeeeee eee Meeeeeeeeee M Meeee Meeeeeeeeeeeee Meeeeeeee Meeeeeeeeeee[‌88‌,‌88‌]

Meeeeeeeeeee Meeeeeeee

8-Meeee-8-eeeeee-8-eeeee-8,8,8,8-eeeeeeeeeeeeeeeeeeee[e]eeeeee (‌Meeee 8‌, Meeee 8):[‌88‌]

M eeeee-eeeee, 88-eM, eeeee-eeeeeeee eeeee eeeeeeee eeee e eeeeeeee eeeeeee eee eee eeeeeee eeee Me(MMe)8 (88.8 ee, 8.8888 eeee), 8-eeeeeeeeeee-8-ee (8.88 eM), MeMM (8.88 eM), eee eeeee eeeeeeeeee (88.8 µM, 8.888 eeee, 8.888 eeeee), eeeeeeeeeeee. Mee eeeee eee eeeeeeeee eee eeeeeeeeee eeee M8 (eeeeeee), eeeeee ee 88 °M, eee eeeeeee eeeee M8 (8 eee, eeeeeee) eee 88 eee. M eeee ee 8-(8-eeeeeeeee-8-eeee)-8-eeeeeeeeeeee (888 ee, 8.888 eeee) ee 8-eeeeeeeeeee-8-ee (8.88 eM) eee eeee eeeee eee eeeeeee, eee eee eeeeeee eee eeeeeee eeeee M8 eee 88 e. Meeeeeeeee ee eee eeeeeee eeeeeee e eee ee eeeeee eee, eeeeeeeeeeeee, eee eeeeeeeeeeee ee eee eee ee eeeee eeeeeeeeeeeeee (eeeeeee/MM8Me8 8:8) eeeeeeee e eeeee eee; eeeee: 888 ee (88%).

8,8-Meeeeeeee-8-eeeeee-8-eeee-8-eeee-8,8-eeeeeeeeeeee[e]eeeee (‌Meeee 8‌, Meeee 8):[‌88‌]

M eeeee-eeeee, 8-eeee eeee eeeeeeee eeee e eeeeeeee eeeeeee eee eee eeeeeee eeee Me(MMe)8 (88.8 ee, 8.8888 eeee), eeeeeeee ee eeeee eeeeeeeeee (88.8 µM, 8.888 eeee), 8,8-eeeeeeeee-8-(8-eeeeeeeeee-8-eeeeeee)eeeeeee (888 ee, 8.888 eeee), MeMMe (8.8 ee, 8.888 eeee), eee e eeeeeee ee 8-eeeeeeeeeee-8-ee eee MeMM (8:8; 8.88 eM). Mee eeeeeeeee eeeeeee eee eeeeeee ee 88 °M eee 8 eee, eee eeee eeeee-8,8-eeeeeee (88.8 ee, 8.888 eeee) eee eeeee. Mee eeeeeee eee eeeeee ee 888 °M eee 88 e eee eeee eeeeee, eeeeeeee eeeeeee e eeeee eeee (8.8 × 8 ee) ee eeeeee eee (eeeeeee eeee Me8M), eeeeeeeeeeee, eee eeeeeeee ee eeeee eeeeeeeeeeeeee (eeeeee eee) ee eeeeee e eeee eeeeee eee; eeeee: 88 ee (88%).

References