1: With tris-(dibenzylideneacetone)dipalladium(0); hypophosphorous ether; 9,9-dimethyl-4,5-bis(diphenyl-phosphino)xanthene in N,N-dimethyl-formamide T=110°C; 15 h; Inert atmosphere; 2: in N,N-dimethyl-formamide T=110°C; 8 h;

chloro-trimethyl-silane; sodium iodide in acetonitrile T=20°C; 16 h; Inert atmosphere;

(i) P(OEt)3, (ii) aq. HCl; Multistep reaction;