A Robust Protocol for the Synthesis of Quinoxalines and 5H-Benzo[e][1,4]diazepines via the Acidless Ugi Reaction
作者:Christopher Hulme、Muhammad Ayaz、Guillermo Martinez-Ariza
DOI:10.1055/s-0033-1339135
日期:——
Concise two-step, one-pot protocols for the syntheses of quinoxalines and 5H-benzo[e][1,4]diazepines are reported. An acidless' Ugi reaction followed by a Boc-deprotection-cyclization sequence is shown to produce arrays of both functionalized scaffolds in good yield. Mono-N-Boc-protected diamines are employed to access quinoxalines and an analogous benzylic amine affords access to 5H-benzo[e][1,4]diazepines in conjunction with supporting reagents in the acidless' Ugi reaction. Both methodologies are robust, straightforward, and allow installation of at least three points of diversity in the resulting scaffolds.