Transition metal catalysed borylation of C-H bonds
Chapter one provides a general review of the metal catalysed diboration of alkynes, 1,2- and 1,3-dienes, a,ß-unsaturated carbonyl compounds, and alkenes, as well as the metal catalysed borylation of alkane and arene C-H bonds. Chapter two is divided into two main sections. The first section introduces a high yield, highly selective catalytic synthesis of vinylboronate esters VBEs, including 1,1-disubstituted VBEs, from alkenes without significant hydrogenation or hydroboration, using the catalyst precursor, trans- [RҺС1(СО)(РРhз)2], and the diboron reagents В2РІП2, В2ПЄОР2 and HBpin. The second section addresses the synthesis of VBEs via microwave-assisted catalysis and these results are compared with those from the conventional, thermal reactions. Chapter three investigates regioselectivity in the synthesis of pyridinyl and bipyridinyl botónate esters via C-H activation using the catalyst precursor, [Іг(СОВ)(ц-ОМе)]2, and 4,4'-'Bu2-2,2'-bipyridine as the ligand. Several the pyridinyl and bipyridinyl boronate esters were coupled with aryl halides by Suzuki-Miyaura cross-coupling reactions in one pot. Examples include msiture-sensitve heteroaryl 2-boronate esters. Chapter four shows the utility of the transition metal catalysed borylation of C-H bonds in the synthesis of biologically active retinoic acid analogs.