240427-50-3

Upstream product

• 100306-33-0 (1R)-3-chloro-1-phenylpropanol 
• 98-53-3 4-tercbutyl-cyclohexanone 
• 168465-69-8 (R)-α-(2-azidoethyl)benzenemethanol 

Downstream Products

• 240427-55-8 (R)-hexahydro-1-(3'-phenyl-3'-propanone)-5-tert-butyl-2H-azepin-2-one 

Relevant academic research and scientific papers

Asymmetric Schmidt reaction of hydroxyalkyl azides with ketones

An asymmetric equivalent of the Schmidt reaction permits stereocontrol in ring expansions of symmetrical cyclohexanones. The procedure involves the reaction of chiral 1,2- and 1,3-hydroxyalkyl azides with ketones under acid catalysis; the initial reaction affords an iminium ether that can be subsequently opened with base. A systematic study of this reaction is reported, in which ketone substrates, chiral hydroxyalkyl azides, and reaction conditions are varied. Selectivities as high as ca. 98:2 are possible for the synthesis of substituted caprolactams, with up to 1,7-stereoselection involved in the overall process. The fact that either possible migrating carbon is electronically identical provides an unusual opportunity to study a ring-expansion reaction controlled entirely by stereoelectronic factors. The mechanism of the reaction and the source of its stereoselectivity are also discussed.

1,7-asymmetric induction in a nitrogen ring expansion process facilitated by in situ tethering

(formula presented) There are only a few methods for the asymmetric ring expansion of prochiral ketones. Symmetrically substituted cyclohexanones can be converted to the corresponding ring-expanded caprolactam with excellent 1,7-diastereoselectivity (≥93%