Formation of pinacol boronate esters via pyridine iodoborane hydroboration.
Hydroboration of alkenes with pyridine iodoborane followed by treatment with pinacol/NaOH affords monoalkyl pinacol boronates in moderate to good yield. Dialkylborinic acid derivatives are formed competitively, especially in the case of terminal alkenes. This side reaction can be minimized by using excess of pyridine iodoborane. More hindered alkenes give the best results.
Karatjas
Andrew G
AG
Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Vedejs
Edwin
E
D000475:Alkenes; D001880:Boranes / Q000737:chemistry*; D001897:Boronic Acids / Q000737:chemistry*; D002625:Chemistry, Organic / Q000379:methods*; D004952:Esters; D017613:Iodine Compounds / Q000737:chemistry*; D007477:Ions; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D011725:Pyridines / Q000737:chemistry*; D013696:Temperature
D000475:Alkenes; D001880:Boranes; D001897:Boronic Acids; D004952:Esters; D017613:Iodine Compounds; D007477:Ions; D011725:Pyridines