Thesis advisor: James P. Morken / This dissertation will discuss in depth four main projects pertaining to the synthesis and utility of organoboronates for the construction of enantioenriched small molecules. First, reaction optimization and substrate scope expansion of the platinum-catalyzed enantioselective diboration of alkenes are reported. Based on extensive experimental and computational mechanistic analysis, a preliminary stereochemical model is also proposed. A practical boron-Wittig reaction is presented in which synthetically challenging di- and trisubstituted vinyl boronates can be accessed in a highly stereoselective fashion from readily available starting materials. The enantioselective diboration of cis- and trans-vinyl boronates furnished novel 1,1,2-tris(boronate) esters in up to 95:5 er. The intermediate tris(boronate) esters were employed successfully in deborylative alkylations to furnish enantioenriched internal vicinal bis(boronates) in excellent diasteoselectivity. In the final chapter, an enantioselective palladium-catalyzed intramolecular Suzuki-Miyaura coupling between allyl boronates and aryl electrophiles is disclosed. The newly developed transformation provides enantioenriched 5, 6, and 7-membered carbocycles in up to 93:7 er. / Thesis (PhD) — Boston College, 2015. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / This dissertation will present four main projects focused on stereoselective construction of borylated compounds as well as their applications in asymmetric syntheses. The first two projects describe the development of a catalytic conjunctive cross-coupling reaction. By merging three simple starting materials, an organolithium reagent, an organoboronate, and an organic electrophile, a synthetically valuable secondary boronate is furnished by the conjunctive cross-coupling in an efficient and enantioselective fashion. Next, this strategy is expanded to synthesize severely hindered tertiary boronates, a synthetic challenging but powerful building block to access a variety of quaternary stereocenters. The third project presents a platinum-catalyzed enantioselective diboration of alkenyl boronates to furnish a broad range of 1,1,2-tris(boronates) products. A deborylative alkylation of the 1,1,2-tris(boronates) leads to a variety of internal vicinal bis(boronates) with high diastereoselectivity. In the final chapter, a general and practical synthesis of alkenyl boronates via the boron-Wittig reaction is disclosed. Utilizing readily accessible geminal bis(boronates) and aldehydes, a broad range of disubstituted and trisubstituted alkenyl boronates are afforded with good yield and stereoselectivity. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.