title: Alkynylation of steroids via Pd-free Sonogashira coupling.
abstract: Cu-catalyzed Pd-free Sonogashira coupling has been proposed as a straightforward and convenient route to valuable steroidal enynes. A biligand catalyst system based on Ph3P and TMEDA has been designed. The protocol was utilized for the efficient coupling of iodosteroids with diverse terminal alkynes and 1-trimethylsilylalkynes. A possible role of an auxiliary ligand as a phase-transfer catalyst for a sparingly soluble inorganic base (K2CO3) was revealed.
authors.affiliation: Chemistry Department, M. V. Lomonosov Moscow State University, 1/3 Leninskiye Gory, Moscow 119991, Russia. nvluk@org.chem.msu.ru.
authors.forename: Yury N
authors.initials: YN
authors.lastname: Kotovshchikov
authors.forename: Gennadij V
authors.initials: GV
authors.lastname: Latyshev
authors.forename: Nikolay V
authors.initials: NV
authors.lastname: Lukashev
authors.forename: Irina P
authors.initials: IP
authors.lastname: Beletskaya