Palladium-catalyzed asymmetric Heck arylation of 2,3-dihydrofuran – effect of prolinate salts
作者:Adam Morel、Ewelina Silarska、Anna M. Trzeciak、Juliusz Pernak
DOI:10.1039/c2dt31672b
日期:——
Chiral ionic liquids (CILs) containing L-prolinate and L-lactate anions and non-chiral quaternary ammonium cations were employed in the palladium catalyzed enantioselective Heck arylation of 2,3-dihydrofuran with aryl iodides (iodobenzene, 4-iodotoluene, 2-iodoanisole, 4-iodoanisole, 4-iodoacetophenone). In all the reactions 2-aryl-2,3-dihydrofuran (3) was obtained as the main product with the yield
含有L-脯氨酸和L-乳酸阴离子和非手性季铵阳离子的手性离子液体(CIL)用于钯催化的对映选择性Heck芳基化。2,3-二氢呋喃 与芳基碘化物(碘苯, 4-碘甲苯, 2-碘苯甲醚, 4-碘苯甲醚, 4-碘苯乙酮)。在所有反应中,获得了2-芳基-2,3-二氢呋喃(3)作为主要产物,收率高达52%,总转化率达到83%。产品3,2-苯基-2,3-二氢呋喃在6小时的反应中,具有出色的对映选择性(> 99%ee), L-脯氨酸四丁基铵。在提出的均相反应中,Pd(0)纳米粒子被视为催化剂的静止状态,并且是催化Heck反应的可溶性钯物质的来源。Heck反应的收率和立体选择性受CIL中非手性阳离子种类的强烈影响。