中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | tert-butyl 5-(2-cyano-3-ethoxy-3-oxo-1-propenyl)-3,4-dimethyl-1H-pyrrole-2-carboxylate | 59435-13-1 | C17H22N2O4 | 318.373 |
The synthesis of symmetric α-free meso-H-dipyrrin hydrobromides from 5-H-2-formyl pyrroles was investigated. The self-condensation produces regioisomeric dipyrrins through adoption of two mechanistic pathways. The key difference between the two pathways lies in which position of the pyrrole directs nucleophilic attack. Through a systematic study involving various substituted and (or) isotopically labelled 5-H-2-formyl pyrroles, we herein provide evidence to suggest that not only do two mechanistic pathways exist, but the steric bulk of the substituent adjacent to the 5-unsubstituted position influences which pathway dominates.