903516-22-3

Basic information

• Product Name: (S)-4-aza-6-(tert-butyldimethylsilanyloxy)-5-benzyl-4-(p-toluenesulfonyl)hexanal dimethyl acetal
• Synonyms: (S)-4-aza-6-(tert-butyldimethylsilanyloxy)-5-benzyl-4-(p-toluenesulfonyl)hexanal dimethyl acetal
• CAS NO: 903516-22-3
• Molecular Weight: 521.794
• Mol File: 903516-22-3.mol
• Article Data: 1

Chemical Properties

• CAS DataBase Reference: (S)-4-aza-6-(tert-butyldimethylsilanyloxy)-5-benzyl-4-(p-toluenesulfonyl)hexanal dimethyl acetal(CAS DataBase Reference)
• NIST Chemistry Reference: (S)-4-aza-6-(tert-butyldimethylsilanyloxy)-5-benzyl-4-(p-toluenesulfonyl)hexanal dimethyl acetal(903516-22-3)
• EPA Substance Registry System: (S)-4-aza-6-(tert-butyldimethylsilanyloxy)-5-benzyl-4-(p-toluenesulfonyl)hexanal dimethyl acetal(903516-22-3)

Safety Data

• Hazardous Substances Data: 903516-22-3(Hazardous Substances Data)

Upstream product

• 3182-95-4 L-Phenylalaninol 
• 98-59-9 p-toluenesulfonyl chloride 
• 82495-70-3 (2S)-2-p-toluenesulfonamido-3-phenylpropanol 
• 96994-77-3 3-iodopropionaldehyde dimethylacetal 
• 143260-53-1 (S)-N-[1-benzyl-2-(tert-butyldimethylsilyloxy)ethyl]-p-toluenesulfonamide 

Downstream Products

• 767288-13-1 (5S)-4-aza-5-benzyl-1-hydroxy-7-oxa-4-(p-toluenesulfonyl)cycloheptane 

Relevant articles and documents

Synthesis of 2,4-disubstituted piperidines via radical cyclization: Unexpected enhancement in diastereoselectivity with tris(trimethylsilyl)silane

A novel approach to 2,4-disubstituted piperidines is reported, involving the radical cyclization of 7-substituted-6-aza-8-bromooct-2-enoates. Cyclization with tributyltin hydride affords the trans piperidines with trans/cis diastereomeric ratios ranging typically from 3:1 to 6:1. Cyclization with tris(trimethylsilyl)silane affords the same products with diastereomeric ratios of up to 99:1 in certain cases. The enhancement in diastereoselectivity results from the selective rearrangement of the minor stereoisomer through a cascade process involving radical cyclization to the piperidine radical, 1,5-radical translocation, and attack of the translocated radical onto the sulfonamide with extrusion of SO2 in a Smiles-type rearrangement. Slower trapping of the piperidine radical by tris(trimethylsilyl)silane compared to tributyltin hydride accounts for the occurrence of the rearrangement cascade in the former case.