Thesis advisor: James P. Morken / The first examples of an enantioselective allene diboration and diene diboration are reported. The asymmetric palladium-catalyzed allene diboration afforded 1,2- bis(boronate)esters in up to 98% ee. The reaction development for the allene diboration, as well as the expansion of the substrate scope, and elucidation of the reaction mechanism are reported. Following the development of the enantioselective allene diboration, the first enantioselective diene diboration was disclosed. 1,4-Dihydroxylation products resulting from a tandem diene diboration/oxidation sequence are obtained in up to 92% ee. / Thesis (PhD) — Boston College, 2008. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / The metal-catalyzed diboration of alkenes has gained fame as a practical methodology for use in the stereoselective construction of complex organic molecules and synthetic building blocks. The created carbon-boron bonds have tremendous versatility and can easily be manipulated into carbon-carbon or carbon-heteroatom bonds. Unfortunately, metal-catalyzed diborations often suffer from limitations such as substrate specificity. To address these issues, we investigated diboration reactions in the absence of transition-metal catalysts. Herein is presented a transition-metal-free, diastereoselective diboration methodology utilizing alkenyl alcohols as substrates. Allylic alcohols can be treated with an organolithium base and bis(pinacolato)diboron to generate 1,2,3-triols upon oxidation. Most studies were done on homoallylic alcohols, which can be performed using a carbonate base and an alcohol additive. This methodology has many strengths, such as a wide substrate scope and high levels of diastereoselectivity. Further investigations into product functionalization and synthetic applications will be pursued in due time. / Thesis (MS) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / Detailed within this dissertation are the developments of novel hydroboration and diboration methodologies to access allylboron reagents and efforts towards the application of these methods in the total synthesis of discodermolide. Chapter 1 describes the development of Ni-catalyzed 1,4-hydroboration of 1,3-dienes with pinacolborane. This method provides synthetically useful allylboron intermediates which can be oxidized to stereodefined (Z)-allylic alcohols or used in stereoselective carbonyl addition reactions. Chapter 2 details the development of Ni-catalyzed 1,4-diboration of 1,3-dienes with bis(pinacolato)diboron. This reaction broadens the scope of 1,4-diboration reactions by including internal and sterically hindered dienes, and proceeds with high 1,4- and (Z)-selectivity. The intermediate allylborons can be oxidized to stereodefined 1,4-diols. Chapter 3 describes the development of diastereoselective Ni-catalyzed 1,4-hydroboration of chiral 1,3-dienols. The reaction provides syn-propionate homoallylic alcohols with stereodefined trisubstituted allylborons for the synthesis of polyketide structures. This methodology, among others, was applied towards the total synthesis of discodermolide. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: Marc L. Snapper / This dissertation will present four main projects that I have been working on since January 2015. The first two chapters will be focusing on the developments of the carbohydrate-catalyzed enantioselective alkene diboraiton. The exchange catalysis between carbohydrate-derived diol catalyst and diboron starting material renders the alkene diboration reaction possible without the aid from transition metals. This successfully brought down the cost for the enantioselective alkene diboration, making it an appealing tool for alkene transformation. Detailed mechanistic study that leads to the reaction efficiency improvements were discussed in chapter 2. The third chapter of this dissertation is about the developments of site-selective oxidation of 1,2-bis(boronate). This is a new type of a reaction motif that the alkene diboration product can undergo. The secondary boronic ester of the 1,2-bis(boronate) was selectively oxidized to hydroxyl group while leaving the primary boronic ester untouched. This new reaction opens up a variety of opportunities to transform 1,2-bis(boronate) into different functional groups. Lastly, in the fourth chapter, recent synthetic methods developed in the Morken group was used in the total synthesis study of complex natural product Amphidinolide C. As it is disclosed, the carbohydrate-catalyzed enantioselective alkene diboration proved to be a powerful transformation either in early stage starting material preparation or in late stage complex structure motif functionalization. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / Described herein are three distinct projects centered on the formation and use of carbon-boron bonds. In the first, the enantioselective platinum-catalyzed 1,4-diboration of trans-1,3-dienes is advanced in both selectivity and scope through the development of a novel class of electron rich chiral monodentate phosphines. Under the action of the new ligands, highly selective diboration is maintained at reduced loadings of catalyst. Secondly, enantioenriched 1,2-bis(pinacol boronates) are engaged in regioselective Suzuki-Miyaura cross-coupling with aryl and vinyl electrophiles. A tandem diboration cross-coupling sequence is successfully implemented to afford homobenzylic and homoallylic pinacol boronates directly from terminal olefins, which subsequently undergo oxidation, amination or homologation of the remaining carbon-boron bond to arrive at a range of enantioenriched products. Lastly, aryl electrophiles containing tethered allylboronate units undergo efficient intramolecular coupling in the presence of a chiral palladium catalyst to give enantioenriched carbocyclic products. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

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Thesis advisor: Kian L. Tan / Thesis advisor: James P. Morken / Described herein are four different research projects spanning over two different research groups. The first two projects describe the development and application of scaffolding catalysts for the (1) site-selective silylation of ribonucleosides and (2) the distal and diastereoselective hydroformylation of homoallylic alcohols. These projects emphasize the effectiveness of scaffolding catalysts to bind a hydroxyl-containing substrate and control the site- or regioselectivity of a reaction using said substrate. The third project describes a hydroxyl-directed diboration of homoallylic and bis-homoallylic alcohols. The hydroxyl-containing 1,2-bis(boronates) are valuable intermediates for further synthetic manipulations. One such manipulation, a hydroxyl-directed Suzuki cross-coupling reaction, is the focus of the final project. This directed cross-coupling reaction forges carbon-carbon bonds in a stereoselective manner, highlighted in the total synthesis of the naturally occurring compound, debromohamigeran E. / 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 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 / Described herein are methods for asymmetric allylation. Chapter 1 describes the scope of the Pd-catalyzed asymmetric diboration of prochiral allenes. The products of this process possess both a chiral allylboronate functional group and a vinylboronate moiety. The allylboronate functionality can subsequently be used for imine allylation, without isolation of the diboron intermediate, resulting in the formation of atypical allylation products through a tandem, one-pot sequence. Furthermore, enantioselection in the catalytic diboration and chirality transfer in the subsequent imine allylation are high; thus, non-racemic, protected homoallylic amines, and other derivatives, are produced in high enantiomeric excess. Chapter 2 describes the discovery and development of a transition-metal-catalyzed asymmetric conjugate allylation of allylboronate ester nucleophiles to activated enones. The scope, utility, and mechanistic aspects of this new reaction are discussed. / Thesis (PhD) — Boston College, 2008. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / Platinum-catalyzed enantioselective 1,4-diboration of cyclic 1,3-dienes is reported, providing enantioenriched 1,4-bis(boronic) esters in good yield and up to 96:4 er. The analogous diboration reaction of imines generated enantioenriched alpha-amino boronic esters, which are valuable therapeutic candidates and useful synthetic building blocks. Alpha-substituted allyl bis(boronic) esters, which are derived from 1,2-diboration of 1,3-dienes, undergo double allylation with 1,4-dicarbonyls to afford cyclic 1,4-diols bearing four contiguous stereocenters in a one-pot fashion with moderate to excellent diastereoselectivity. The development of a synthesis of geminal bis(boronic) esters is disclosed. These unique compounds were utilized in an alkoxide-promoted deborylative alkylation to access primary, secondary and tertiary boronic esters. / Thesis (PhD) — Boston College, 2015. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.