Me-BIPAM for the Synthesis of Optically Active 3-Aryl-3-hydroxy-2-oxindoles by Ruthenium-catalyzed Addition of Arylboronic Acids to Isatins

作者：Yamamoto Yasunori^*; Yohda Masaaki; Shirai Tomohiko; Ito Hajime; Miyaura Norio

来源：Chemistry-An Asian Journal, 2012, 7(10): 2446-2449.

DOI：10.1002/asia.201200481

• 1
• 2-addition
• 3-substituted-3-hydroxy-2-oxindole
• boron
• isatin
• ruthenium

A chiral O-linked C2-symmetric bidentate phosphoramidite (Me-BIPAM) was found to be efficient for the ruthenium-catalyzed addition of arylboronic acids to isatins. Asymmetric synthesis of 3-aryl-3-hydroxy-2-oxindoles by 1,2-addition of arylboronic acids to isatins was carried out in the presence of [RuCl2(PPh3)3]/(R,R)-Me-BIPAM and KF, resulting in an enantioselectivity as high as 90?% ee. It was found that the reaction with N-protected isatins proceeds with high yields and good enantioselectivities. The best protective groups on the nitrogen atom were different depending on the substituents on the aromatic ring. The use of a N-benzyl group resulted in excellent enantioselectivities in many substrates compared with other groups.

• 出版日期2012-10