Formation of New Chiral Carbons

Any reaction that creates a new bond to an achiral carbon has the potential to create a new chiral center if that carbon has a tetrahedral geometry in the product. Examples in which the starting carbon was also tetrahedral include free-radical halogenation (replace H- with X-) and a-alkylation of an enolate 

Introduction to Strategies for Organic Synthesis, First Edition. Laurie S. Starkey. 2012 John Wiley Sons, Inc. Published 2012 by John Wiley Sons, Inc. 

Achiral Starting Materials Give Racemic Mixtures 

Starting material, it must be formed as a racemic mixture, so a total of four stereoisomers will be produced. This may seem complex, but it is a common occurrence in chemistry. 

Diastereomeric Transition States Lead to Unequal Mixtures 

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