title: Cobalt-Catalyzed Cross-Coupling of Grignards with Allylic and Vinylic Bromides: Use of Sarcosine as a Natural Ligand.
abstract: Sarcosine was discovered to be an excellent ligand for cobalt-catalyzed carbon-carbon cross-coupling of Grignard reagents with allylic and vinylic bromides. The Co(II)/sarcosine catalytic system is shown to perform efficiently when phenyl and benzyl Grignards are coupled with alkenyl bromides. Notably, previously unachievable Co-catalyzed coupling of allylic bromides with Grignards to linearly coupled α-products was also realized with Co(II)/sarcosine catalyst. This method was used for efficient preparation of the key intermediate in an alternative synthesis of the antihyperglycemic drug sitagliptin.
authors.affiliation: †Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia.
authors.forename: Rok
authors.initials: R
authors.lastname: Frlan
authors.affiliation: †Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia.
authors.forename: Matej
authors.initials: M
authors.lastname: Sova
authors.affiliation: †Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia.
authors.forename: Stanislav
authors.initials: S
authors.lastname: Gobec
authors.affiliation: ‡API Development, Organic Synthesis Department, Lek Pharmaceuticals, d.d., Sandoz Development Centre Slovenia, Kolodvorska 27, 1234 Mengeš, Slovenia.
authors.forename: Gaj
authors.initials: G
authors.lastname: Stavber
authors.affiliation: †Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia.|‡API Development, Organic Synthesis Department, Lek Pharmaceuticals, d.d., Sandoz Development Centre Slovenia, Kolodvorska 27, 1234 Mengeš, Slovenia.|§Global Portfolio Management API, Sandoz GmbH, Biochemiestrasse 10, 6250 Kundl, Austria.
authors.forename: Zdenko
authors.initials: Z
authors.lastname: Časar
mesh_terms: D000498:Allyl Compounds / Q000737:chemistry*; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry; D007004:Hypoglycemic Agents / Q000737:chemistry* / Q000494:pharmacology; D007202:Indicators and Reagents; D008024:Ligands; D015394:Molecular Structure; D012521:Sarcosine / Q000737:chemistry*; D000068900:Sitagliptin Phosphate / Q000737:chemistry* / Q000494:pharmacology; D014753:Vinyl Compounds / Q000737:chemistry*
chemical_list: D000498:Allyl Compounds; D007004:Hypoglycemic Agents; D007202:Indicators and Reagents; D008024:Ligands; D014753:Vinyl Compounds; D003035:Cobalt; C003763:vinyl bromide; C050431:allyl bromide; D000068900:Sitagliptin Phosphate; D012521:Sarcosine