Synthesis of substituted indoles via a highly selective 7-lithiation of 4,7-dibromoindoles and the effect of indole-nitrogen on regioselectivity
摘要:
We have developed an efficient synthetic pathway to rapidly access 4-bromoindoles, 4-substituted indoles, 4-bromo-7-substituted indoles, and 4,7-disubstituted indoles using a highly selective lithiation at the 7-position of 1-alkyl-4,7-dibromoindoles when treated with t-BuLi in ether. Based upon the selectivity obtained with 5,7-dibromoindoles in our previous study and with 4,7-dibromoindoles in the current study, we conclude that the alkylated indole nitrogen plays an important role in controlling selectivity. (C) 2003 Elsevier Ltd. All rights reserved.
Synthesis of substituted indoles via a highly selective 7-lithiation of 4,7-dibromoindoles and the effect of indole-nitrogen on regioselectivity
摘要:
We have developed an efficient synthetic pathway to rapidly access 4-bromoindoles, 4-substituted indoles, 4-bromo-7-substituted indoles, and 4,7-disubstituted indoles using a highly selective lithiation at the 7-position of 1-alkyl-4,7-dibromoindoles when treated with t-BuLi in ether. Based upon the selectivity obtained with 5,7-dibromoindoles in our previous study and with 4,7-dibromoindoles in the current study, we conclude that the alkylated indole nitrogen plays an important role in controlling selectivity. (C) 2003 Elsevier Ltd. All rights reserved.