Science of Synthesis

Zhang, M.; Su, W., Science of Synthesis: Cross Coupling and Heck-Type Reactions, (2013) 3, 107.

To avoid forming a stoichiometric amount of salt waste in Mizoroki–Heck reactions, a palladium-catalyzed decarbonylative coupling of arenecarboxylic anhydrides with alkenes has been developed. This procedure, which represents the first example of a base-free reaction,[‌7‌] is carried out in 1-methylpyrrolidin-2-one in the presence of palladium(II) chloride (0.25 mol%) as the catalyst. A catalytic amount of sodium bromide (1 mol%) is found to significantly improve the efficiency of the reaction, which, in addition to the desired alkenes ‌10‌ and ‌11‌, produces only carbon monoxide and a carboxylic acid as byproducts. In principle, the former can be easily burnt to give nontoxic carbon dioxide and the latter can be recycled into its corresponding anhydride. Furthermore, the method is applicable to a variety of alkenes under similar conditions at temperatures ranging from 140 to 190 °C (‌Scheme 5‌). Alkenes bearing electron-withdrawing groups generally afford β-arylated products in good yields, and both terminal and internal alkyl-substituted alkenes can serve as the substrate, giving a mixture of isomeric alkenes favoring the E-form.

‌Meeeee 8‌ Meeeeeeee-Meeeeeeee Meeeeeee ee Meeeeeeeeeeeeee Meeeeeeeee eeee Meeeeee[‌8‌]

‌Meeeeeeeeee 8‌

e Meeee ee eee eeeeeeee eeeeee eeeeeee.

‌Meeeeeeeeee 8M‌

e Meeee ee eee eeeeeeee eeeeee eeeeeeee.

Mee eeeeeeeee ee eeee-eeeeeeeeeee M-eeeeeee ‌88‌ ee eeeeeeeee-eeeeeeeee eeeeeeeeeeeeeee eeeeeeee ee eeeeeee eeee eeeee eeeeeeeeee, eeeeeeee ee ee eeee eeeeeeeeee ee eee eeeeeeeeeeeee eeeeeeeeee eeeee eeee ee-eeee-eeeee eeeeeeeeeee, eee eeee eeeeeeee (‌Meeeee 8‌).[‌8‌] Meee eeeeee eee eeeeeee eee eeeeee eee ee eeeeeeeeeeeeeee eeeee, eeeeeeeeeee eee eeee eee eee eeeee eeeeeeeeeee ee eeee eeeeeeeeeee. Me eeeeeeeeee eeeeee, 8-eeeeeeeeeeeeee (γ-eeeeeeee), ee eeee eeeeeeee ee eeeee eee eeeeeeeeeeeee ee eee eeeeeeeee eeeeeeee, eeee eeeeeeeeee eee eeeeeeee. M eeeeeee ee eeeeeeeeeeeeee eeeee- eee eeeeeeeeeeeeeeeeee eeeee eeee eeee eeee ee eeeeeeeeee eee eeee eeeeeeeeeeeeee.

‌Meeeee 8‌ Meeeeeeee-Meeeeeeee Meeeeeee ee Meeee Meeeeeeeee eeee Meeeeee[‌8‌]

‌Meeeeeeeeee 8‌

Me8	M8	Meeeeeeeeee Meeeee	Meeeee (%)	Mee
Me	Me	88:8	88	[‌8‌]
8-MeMM8M8	Me	88:8	88	[‌8‌]
8-eeeeeeee	Me	88:8	88	[‌8‌]
8-Mee	Me	88:8	88	[‌8‌]
8-MeM8M8	Me	88:8	88	[‌8‌]
8-eeeeeee	Me	88:8	88	[‌8‌]
8-MM8M8	Me	88:8	88	[‌8‌]
8,8,8-(MeM)8M8M8	Me	88:8	88	[‌8‌]
8-MeMM8M8	Me	88:8	88	[‌8‌]
8-eeeee	Me	88:8	88	[‌8‌]
8-eeeee	Me	88:8	88	[‌8‌]
8-eeeeeee	Me	88:8	88	[‌8‌]
Me	MM8e-Me	88:8	88	[‌8‌]
Me		8:8	88	[‌8‌]

e Meeee ee 8,8-/8,8-eeeeeeeeeeeee eeeeeee.

e Meeee ee eeeeeeee eeeeee eeeeeee.

Meeeeeeeeeee Meeeeeeee

Meeeeee (M/M)-8-Meeeeeeee-8-eee-8,8-eeeeee (‌88M‌/‌88M‌, M8 = M8 = MM8Me; M8 = M); Meeeeee Meeeeeeee:[‌8‌]

M Meeeeee eeee (888 eM) eeeeee eeee e eeeeee eeeeee eeeee eee eeeeeeee eeee e eeeeeeee eeeeeee eee eee eeeeeee eeee Me8M (88 e, 888 eeee), MeMe8 (88 ee, 8.88 eeee), eee MeMe (888 ee, 8.8 eeee). Meeee eeeeeeee eeeeeeeee eeeee eeeeee eee eeeeeee eeee eeeee, eeeeeee eeeee (88 eeee) eee eeeee ee ee eeeeeeee eeeeeeee, eeeeeeee eeeeeeeeeeee ee eeeeeee (M)-eee-8-eee-8,8-eeeeee (88.8 eM, 888 eeee) eee MMM (888 eM). Mee Meeeeee eeee eee eeeeee ee 888 °M eee 8 e, eee eee eeeeee ee eee eeeeeeee eee eeeeeeeee ee MM (MM-Mee 8 MM eeeeee). Meeeeeeeee eeeeeeeeeeee ee eee eeeee eeeeeee (888 °M/8 Meee) eeee eee eeeeeee ee e eeeeeee ee eeeeeeeeeeeee [eeeee (‌88M‌/‌88M‌) 8:8]; eeeee: 88%.

(M)-Meeeeeee (‌88‌, Me8 = M8 = Me); Meeeeee Meeeeeeee:[‌8‌]

M 88-eM eeeee eee eeeeeee eeee MeMe8 (8.88 ee, 8.88 eeee), MeMM (888 ee, 8.8 eeee), eeeeeee (888 µM, 8.8 eeee), Mee8M (888 ee, 8.8 eeee), MeMe (8.8 ee, 8.8 eeee), 8-eeeeeeeeeeeeee (88.8 µM, 8.8 eeee), eee eee MMM (8 eM). Mee eeeeeeeee eeeeeee eee eeeeee eeee eeeee eee eeeeee ee 888 °M, eee ee eeeeee ee Mee8M (888 ee, 8.8 eeee) ee MMM (8 eM) eee eeee eeeee eeeeee eee eeeeeee eeee eeee eeeeeee eeeee. Meeee 88 e, eee eeeee eeeeeee eee eeeeeee eeee eeeeeee (88 eM) eee eeeeee eeee 8 M MMe (88 eM), M8M (88 eM), eee eee. ee MeMMM8 (88 eM). Mee eeeeeee eeeee eee eeeee (MeMM8) eee eee eeeeeeeee eeee eeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeee eeeeeeee eee eeeeeeee eeeeeee e eeeee eeee ee eeeeee eee eeeee eeeeee ee eee eeeeee ee eeee eee eeeeeee eee eeeee eeeeeeeeee ee eee eeeeeeeeeee [eeeee (8,8-/8,8-eeeeeeeeeeee) 88:8]; eeeee: 888 ee (88%).

References