Diastereoselective electrophilic α-amination of camphor N1-acyl N2-phenylpyrazolidinones: the metal enolate-dependent synthesis of two possible hydrazide diastereomers

Autor:	Chin Sheng Chao, Chung Kai Cheng, Kwunmin Chen, Ssu Hsien Li
Rok vydání:	2009
Předmět:	Chiral auxiliary Organic Chemistry Diastereomer Hydrazide Biochemistry Medicinal chemistry chemistry.chemical_compound Camphor chemistry Drug Discovery Electrophile Stereoselectivity Enantiomer Amination
Zdroj:	Tetrahedron Letters. 50:333-336
ISSN:	0040-4039
DOI:	10.1016/j.tetlet.2008.11.003
Popis:	Complementary approaches under enolate amination reactions for the synthesis of both α-hydrazidoacyl diastereomers have been achieved. Both isomers are obtained with high to excellent chemical yields and high stereoselectivities (up to >95:5 dr) when aryl-substituted camphor N1-acyl N2-phenylpyrazolidinone was treated with potassium hexamethyldisilylamide (KHMDS) and lithium hexamethyldisilylamide (LHMDS), respectively, followed by the addition of di-tert-butyl azodicarboxylate. The nondestructive removal of the chiral auxiliary, which can be carried out under mild condition, afforded the hydrazido alcohol with high enantiomeric ratio. The facial stereoselectivity and stereochemical course of the reactions are discussed.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::321420c4ea9978d85768b41819e70328 https://doi.org/10.1016/j.tetlet.2008.11.003 Zobrazit plný text záznamu Full Text from ScienceDirect