Increasing appendage diversity on 3,4-dihydro-3-oxo-2H-1,4-benzoxazines via Aphos–Pd(OAc)2-catalyzed Suzuki–Miyaura cross-coupling of aryl chlorides
摘要:
A library of 32 members of 3,4-dihydro-3-oxo-2H-1,4-benzoxazines has been synthesized from two substituted 2-aminophenols via microwave-assisted one-pot regioselective annulation of 2-bromoalkanoates and subsequent Suzuki-Miyaura cross-coupling of the chloro-substituted scaffolds. The latter transformation was carried out using our Aphos-Pd(OAc)(2) catalyst and the coupling of the aryl chlorides with arylboronic acids proceeded under mild reaction conditions at 60-80 degrees C in THF-H2O (10:1) in the presence of K3PO4 center dot 3H(2)O as the base to furnish the corresponding biaryl products in 80-98% yields. (C) 2013 Elsevier Ltd. All rights reserved.
Increasing appendage diversity on 3,4-dihydro-3-oxo-2H-1,4-benzoxazines via Aphos–Pd(OAc)2-catalyzed Suzuki–Miyaura cross-coupling of aryl chlorides
摘要:
A library of 32 members of 3,4-dihydro-3-oxo-2H-1,4-benzoxazines has been synthesized from two substituted 2-aminophenols via microwave-assisted one-pot regioselective annulation of 2-bromoalkanoates and subsequent Suzuki-Miyaura cross-coupling of the chloro-substituted scaffolds. The latter transformation was carried out using our Aphos-Pd(OAc)(2) catalyst and the coupling of the aryl chlorides with arylboronic acids proceeded under mild reaction conditions at 60-80 degrees C in THF-H2O (10:1) in the presence of K3PO4 center dot 3H(2)O as the base to furnish the corresponding biaryl products in 80-98% yields. (C) 2013 Elsevier Ltd. All rights reserved.