9,9-dimethyl-4,5-bis(diphenyl-phosphino)xanthene; sodium t-butanolate; tris(dibenzylideneacetone)dipalladium (0) in isopropyl alcohol; toluene T=85°C;

1.1: NaHMDS / tetrahydrofuran / 0.17 h / -10 °C 1.2: 81 percent / tetrahydrofuran / 0.5 h 2.1: 67 percent / t-BuONa; XantPhos / Pd2(dba)3 / toluene; propan-2-ol / 85 °C View Scheme

T=150 - 210°C;