Scheme 215. π-Extended Ullazine with a Benzoisoindole Core.
Reagents and conditions: (a)408 for 215.2a: n-BuLi, triisopropylsilylacetylene, THF, 0 °C to rt, 3 days, 215.2b: phenyllithium, THF, rt, 3 days, 215.2c: n-BuLi, 2-bromobenzothiophene, THF, −78 °C to rt, 3 days; (b) SnCl2, DCM, rt, 3 days.