Preparation of 2,4,5-trisubstituted pyrazolo[4,3-c]quinolin-3-ones
摘要:
The preparation of pyrazolo[4,3-c]quinolinones is reported starting from 2-substituted-5-(2-fluorophenyl)-3-oxo-2,4-dihydro-3H-pyrazol-3-ones. A one-pot protocol was developed, in which condensation with an orthoamide, followed by substitution with a primary amine and subsequent S(N)Ar-cyclization, to provide rapid access to 4- and 5-substituted pyrazolo[4,3-c]quinolinones. (C) 2009 Elsevier Ltd. All rights reserved.
Preparation of 2,4,5-trisubstituted pyrazolo[4,3-c]quinolin-3-ones
摘要:
The preparation of pyrazolo[4,3-c]quinolinones is reported starting from 2-substituted-5-(2-fluorophenyl)-3-oxo-2,4-dihydro-3H-pyrazol-3-ones. A one-pot protocol was developed, in which condensation with an orthoamide, followed by substitution with a primary amine and subsequent S(N)Ar-cyclization, to provide rapid access to 4- and 5-substituted pyrazolo[4,3-c]quinolinones. (C) 2009 Elsevier Ltd. All rights reserved.
Asymmetric synthesis of atropisomeric pyrazole <i>via</i> an enantioselective reaction of azonaphthalene with pyrazolone
作者:Huijun Yuan、Yao Li、Hanhui Zhao、Zhihong Yang、Xin Li、Wenjun Li
DOI:10.1039/c9cc06360a
日期:——
The first catalytic asymmetricreaction of azonaphthalene with pyrazolone has been established. A wide range of axially chiral pyrazole derivatives have been achieved in good yields (68–99%) with excellent enantioselectivities (83–98% ee) by utilizing chiral phosphoric acid as a catalyst. This strategy provides an efficient and facile approach for the construction of axially chiral pyrazole derivatives