Intramolecular [2+2+2] cycloaddition of bis(propargylphenyl)carbodiimides: synthesis of L-shaped π-extended compounds with pyrrolo[1,2-a][1,8]naphthyridine corner units†
Abstract
L-shaped π-extended penta-, hexa-, and heptacycles with a pyrrolo[1,2-a][1,8]naphthyridine junction were prepared from N,N′-bis[2-(2-alkyn-1-yl)phenyl]carbodiimides or their