A combination of an achiral pyridoxal analogue and a chiral base has been developed for catalytic deuteration of L-alanine with inversion of stereochemistry to give deuterated D-alanine under mild conditions (neutral pD and 25 °C) without the use of any protecting groups. This system can also be used for catalytic deuteration of D-alanine with retention of stereochemistry to give deuterated D-alanine. Thus a racemic mixture of alanine can be catalytically deuterated to give an enantiomeric excess of deuterated D-alanine. While catalytic deracemization of alanine is forbidden by the second law of thermodynamics, this system can be used for catalytic deracemization of alanine with deuteration. Such green and biomimetic approach to catalytic stereocontrol provides insights into efficient amino acid transformations.

Laboratory-based learning can be weakened by a lack of connection with underlying theory and limited contextualization to enhance motivation. To address these shortcomings, a framework for the development of web-based multimedia prelaboratory modules is proposed. The framework incorporates supportive information (content), utility value (context), multimedia design principles (design), and questions/explanatory feedback (formative assessment). On the basis of this framework, prelaboratory modules were developed for three second-year organic chemistry experiments in a chemical engineering course. Each module consists of a few short animation videos and a few questions. The videos include explanation of theories and justification for experimental procedures (supportive information), as well as explanation of utility value to increase student motivation. The effectiveness of the modules was assessed through multiple strategies including a survey with learning and utility value/motivation constructs, student grades for the modules, time spent on the modules, and the number of times videos were watched. Students in general expressed positive views regarding the prelaboratory modules in terms of understanding and relating theory to procedures, and understanding the utility value of the material. Half of the students reported increased motivation as a result of understanding the utility value of the knowledge they acquired. Thus, prelaboratory exercises based on this framework may alleviate some of the educational challenges in undergraduate laboratories.

The highly stereoselective supramolecular self-assembly of α-amino acids with a chiral aldehyde derived from binol and a chiral guanidine derived from diphenylethylenediamine (dpen) to form the imino acid salt is reported. This system can be used to cleanly convert D-amino acids into L-amino acids or vice versa at ambient temperature. It can also be used to synthesize α-deuterated D- or L-amino acids. A crystal structure of the ternary complex together with DFT computation provided detailed insight into the origin of the stereoselective recognition of amino acids.

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Reaction between 1,2-bis(2-hydroxyphenyl)-ethylenediamine (hpen) and methyl pyruvate gives the diaza-Cope rearrangement product with good yield and excellent stereospecificity. The product containing two chiral quaternary carbon centers is characterized by high performance liquid chromatography and X-ray crystallography. DFT computation provides insight into why the diaza-Cope rearrangement takes place readily with methyl pyruvate but not with other ketones like acetone and substituted acetophenones.