Rhodium-Catalyzed 1,4-Addition of Arylboronic Acids to α,β-Unsaturated Carbonyl Compounds: Large Accelerating Effects of Bases and Ligands
作者:Ryoh Itooka、Yuki Iguchi、Norio Miyaura
DOI:10.1021/jo0207067
日期:2003.7.1
phosphine derivatives. The reaction was further accelerated in the presence of KOH, thus allowing the 1,4-addition even at 0 degrees C. A cationic rhodium(I)-(R)-binap complex, [Rh(R-binap)(nbd)]BF(4), catalyzed the reaction at 25-50 degrees C in the presence of Et(3)N with high enantioselectivities of up to 99% ee for alpha,beta-unsaturated ketones, 92% for aldehydes, 94% for esters, and 92% for amides.
重新研究了铑(I)催化的芳基硼酸向α,β-不饱和羰基化合物的1,4-加成反应中的配体和碱的影响,以在温和的条件下进行该反应。与相应的铑-acac或-氯配合物及其膦相比,具有1,5-环辛二烯(鳕鱼)和羟基配体如[RhOH(cod)](2)的铑(I)配合物表现出优异的催化剂活性。衍生品。在KOH的存在下,反应进一步加速,因此甚至在0摄氏度下也可以进行1,4-加成。阳离子铑(I)-(R)-双酚络合物[Rh(R-binap)(nbd)] BF(4)在Et(3)N存在的情况下,在25-50摄氏度的条件下催化反应,对于α,β-不饱和酮,对映选择性高达99%ee,对于醛,对于醛而言,高达92%,对于酯而言,高达94%,酰胺为92%。