Thesis advisor: Kian L. Tan / Utilization of catalytic directing groups in the regioselective hydroformylation of 1,2-disubstituted olefins and in the site-selective functionalization of 1,2-diols. Chapter One: Catalytic directing groups for the regioselective hydroformylation of allylic alcohols. Chapter Two: Scaffolding catalysis as an alternate and more practical solution to the site-selective functionalization of 1,2-diols. / Thesis (MS) — Boston College, 2011. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

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Thesis (Eng.D.)--City University of Hong Kong, 2009. / "Submitted to Department of Building and Construction for the degree of Engineering Doctorate." Includes bibliographical references (leaves 185-191)

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 105). Also available in electronic version. Access restricted to campus users.

Thesis advisor: Kian L. Tan / Chapter 1. The use of directing groups is a powerful way to control selectivity in organic chemistry. Due to their ability to install new functionality in a reliable fashion, directing groups have had a profound impact on stereoselective, site-selective, and regioselective transformations. More recently, catalytic directing groups have been developed and utilized in a variety of metal-catalyzed transformations, including C-H activation and hydroacylation, and have the potential to be more broadly applied to other transformations. Chapter 2. Catalytic directing groups have recently been designed for hydroformylation. Based on the design of racemic scaffolding ligand 2.5, enantioenriched ligand 2.42 was synthesized for the asymmetric hydroformylation of para-methoxyphenyl (PMP) protected allylic amines. Under mild conditions, a variety of 1,2-disubstituted olefins underwent directed hydroformylation to afford the proximal β-amino alcohol products in good yields and excellent enantioselectivities. The substrate scope has been extended to electronically modified allylic anilines. A modest resonance effect was seen upon the aniline substrate binding to the ligand, which, in turn, manifested in the hydroformylation reaction results. Thus the first enantioselective reaction performed with a catalytic directing group was demonstrated. Chapter 3. Ligand 3.67 was developed, which promotes aldehyde formation on the distal olefinic carbon relative to the directing functionality on the substrate. This is in contrast to other phosphorus-based directing groups that have been successful at placing the aldehyde on the proximal olefinic carbon. Ligand 3.67 has been applied to the diastereoselective hydroformylation of homoallylic alcohols to afford δ-lactones selectively. Altering the distance between the alcohol and olefin revealed that homoallylic alcohols afford the distal lactone with the highest levels of regioselectivity. Taken together with previous examples of proximal-selective hydroformylation, these results being to more fully address the challenge of controlling regioselectivity in hydroformylation. Chapter 4. The harvesting of energy from light to power chemical transformations is an underdeveloped area. Utilizing p-type silicon nanowires (SiNWs) as a photocathode, the photoelectrochemical carboxylation of aromatic ketones has been developed to afford α-hydroxy carboxylic acids. Utilizing low operating potentials, the direct reduction of carbon dioxide (CO2) is avoided. Highlighting the synthetic utility of this transformation, two precursors to the NSAID compounds ibuprofen and naproxen were synthesized using CO2, and abundant C1 feedstock, and light, a crucial source of energy in nature. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: Kian L. Tan / Chapter 1. Directing groups are a powerful means of controlling the selectivity in reactions. The field of hydroformylation has used directing group strategies to control regio- and diastereoselectivity with much success. However, directing groups are inherently inefficient as they must be installed and removed from the molecule of interest, and generate a stoichiometric byproduct in the process. Strategies to solve this problem have included the use of exchange reactions that allow for transient binding of substrate to a molecule that can direct the course of the reaction. This allows the use of catalytic quantities of the directing functionality to effect the desired transformation, and obviates the need for installation and removal of the directing functionality in separate steps. Chapter 2. Our lab has developed a phosphorous based ligand that incorporates an N,O-acetal moiety that allows for reversible binding of both alcohol substrates and a metal catalyst. These ligands rapidly exchange with alcohols in the presence of catalytic amounts of p-TsOH. The racemic ligand was found to undergo epimerization on exchange with a chiral alcohol in an effort to isolate enantioenriched material. However, a strategy using a thermodynamic gearing effect of adjacent stereocenters was found to be successful in producing a chiral ligand. Chapter 3. Using catalytic quantities of our scaffolding ligand we are able to effect branch- and diastereoselective hydroformylation of homoallylic alcohols. We offer a model based on A1,3 strain for the origin of the diastereoselectivity, and tested substrates to lend support to the model. We also investigated the use of chiral scaffolding ligands in the enantioselective hydroformylation of homoallylic alcohols, and preliminary results show modest enantioselectivity. Chapter 4. We have expanded the substrate scope of our scaffolding ligand strategy to include the hydroformylation of allylic alcohols. We are able to produce β-hydroxy carbonyl compounds in good yields and with excellent selectivities, which offers an alternative to the formaldehyde aldol reaction. We show that our strategy is successful in the hydroformylation of trisubstituted olefins, which are a difficult class of hydroformylation substrates, where we are able to produce single diastereomers in good yields under mild conditions. We investigated the enantioselective hydroformylation of allylic alcohols and found that while racemization may be a problem with these substrates, in-situ hemi-acetal protection may offer a solution to the problem. / Thesis (PhD) — Boston College, 2011. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Self-regulated learning (SRL) processes are frequently used by elite athletes and are thought to be an important factor in the development of expertise (McCardle, Young, & Baker, 2017). Before learners become self-regulated, they must first be co-regulated by a more experienced other (Glaser, 1996), such as an instructor. Scaffolding, a form of co-regulation, has three conceptual characteristics: contingency, fading, and transfer of responsibility (van de Pol & Elbers, 2013). Of the little research done on scaffolding, most studies have been in the education domain with few looking at it in a naturalistic setting. This thesis represented a seminal investigation on the nature of scaffolding in a coach-athlete dyad. It aimed to explore scaffolding using a naturalistic, instrumental case study with an experienced female coach (aged 53, national level) and her competitive male figure skater (aged 15, provincial level) using a concurrent mixed methods design (Creswell, 2003). Data were collected through a) an athlete self-report survey on SRL at the beginning and end of data collection; b) participant observation, field notes, and audio recordings of coach-skater dialogue at 16 practices spread across 5 months of the season; and c) three separate interviews at mid-, late-, and post-season with the coach and skater. Study 1 presents results informed by the skater’s survey and quantitative analyses of audio transcripts. The skater’s self-report of the SRL-SP (Bartulovic, Young, & Baker, 2017) was higher at time two (post-season) compared to time one (mid-season), indicating an increase in SRL. Due to very poor reliability uncovered in pilot work, planned analyses to determine changes in the directionality of coach- and skater-initiated discussion and contingency at various points across the season could not be performed. Study 2 presents the results of thematic analysis (Braun & Clarke, 2006) on the interview data and audio transcript excerpts. Deductive analyses showed it was difficult to identify and describe aspects of the three scaffolding characteristics separately due to their overlapping conceptual definitions, and their interplay during practice. Inductive analyses revealed nuances of scaffolding in sport, including micro- and macro-level co-regulation. Micro-level co-regulation emerged as an important “interface” illustrated by mature coach-skater interactions surrounding practice trials. The interface involved shared and individual expectations for the coach and skater, roles, and described transitory processes relating the co-regulatory interface to the skater’s SRL. Fading in sport differed from the linear model in education with a cyclical pattern of engagement by the coach, returning to refine the skater’s elements if they were incorrect. After integrating and interpreting all the data, the findings suggested scaffolding manifests in unique ways in a sport dyad, with SRL representing a process goal of the interface.

Thesis (B.Sc)--University of Hong Kong, 2005. / Includes bibliographical references (p. 183-189)

A study for scaffolding strategies in the project approach for kindergarten teacher Abstract The purpose of this research is an inquiry for kindergarten teachers¡¦ implement of project approach and types of scaffolding strategies. This study used qualitative research methods, with an implementation project approach for early childhood teacher. Through the way of participation in observation, collect project approach interaction and dialogue, and analysis of inductive teaching scaffolding strategies types. In addition, analysis of interviews with the teacher implementation project approach, while collecting important files, classes for data of triangular detection. The conclusions of this study provided as follows: First, preschool teachers in the implementation of a project approach, in the course of their choice of topic is consistent with the child's interest. Chard (1998), proposed five features to review teachers implementation topics course of history, their schema definition, and structural characteristics, helping children's physical and mental development. Project approach teachers in topic scenarios enhance early childhood learning and improve mental development. Second, demonstrate seven types of scaffolding strategies, including language-scaffold being most often introduced. Teachers used scaffold strategy to assist in the construction of knowledge, or to construct preschool curriculum orientation. Third, teachers with scaffold strategies, certainly help young children learning. The effectiveness of teacher practical knowledge and capacity enhancement, cognitive schema provides a learning environment. The attitude of parents is another factor of obstacles. Finally, prevalent in present, manpower shortage problem led to the heavy workload for the teachers in the kindergartens. Eventually, it is worth concerning the teaching time was deprived and the teaching quality and effectiveness was affected as well.

Thesis (Ph.D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008. / Committee Chair: Weck, Marcus; Committee Member: Bunz, Uwe H. F.; Committee Member: Dickson, Robert M; Committee Member: Fahrni, Christoph J; Committee Member: Jones, Christopher W; Committee Member: Murthy, Niren.