A General Method for the Vinylation of Nitrones. Synthesis of Allyl Hydroxylamines and Allyl Amines
摘要:
An examination of the vinylation of several nitrones is presented. Whereas a complete diastereofacial discrimination was observed upon the addition of vinyl organometallic reagents to alpha-alkoxy nitrones, the same reaction with alpha-amino nitrones pave syn adducts in all cases, with the only exception of a L-serine-derived alpha-amino monoprotected nitrone. The obtained allyl hydroxylamines were easily transformed into synthetically valuable allyl amines.
Highly diastereoselective nucleophilic addition of organometallic reagents to 2-pyrrolidinyl nitrones: a semiempirical approach
作者:Pedro Merino、Santiago Franco、Jose M. Gascon、Francisco L. Merchan、Tomas Tejero
DOI:10.1016/s0957-4166(99)00203-7
日期:1999.5
2-Pyrrolidinyl nitrones 1 and 2 derived from l-proline and trans-4-hydroxy-l-proline, respectively, undergo nucleophilic additions of Grignard reagents and organolithium compounds with high syn selectivity, to yield enantiomerically pure pyrrolidinyl benzyl hydroxylamines. A rationale for the observed stereoselectivity based on semiempirical calculations is presented.
O -Silyl triflate-promoted addition of diethyl phosphite to chiral aldonitrones. A rapid access to complex α-amino phosphonates and their N -hydroxy derivatives
作者:Carmela De Risi、Alessandro Dondoni、Daniela Perrone、Gian Piero Pollini
DOI:10.1016/s0040-4039(01)00363-x
日期:2001.4
The addition reaction of diethyl phosphite to O-silylated N-benzyl nitrones derived from chiral alpha -alkoxy and N-Boc alpha -amino aldehydes has been studied as a stereoselective carbon-phosphorus bond forming process for the synthesis of polyhydroxylated alpha -amino and alpha,beta -diamino phosphonates. Key intermediates are the corresponding N-hydroxy alpha -amino phosphonates. (C) 2001 Elsevier Science Ltd. All rights reserved.
A New and Expedient Diastereoselective Synthesis of α-(Hydroxyamino)phosphonates and α-Aminophosphonates by Silyl Triflate Promoted Diethyl Phosphite Addition to Chiral N-Benzyl Nitrones
作者:Carmela De Risi、Daniela Perrone、Alessandro Dondoni、Gian Piero Pollini、Valerio Bertolasi
DOI:10.1002/ejoc.200200698
日期:2003.5
efficient methodology for the synthesis of α-aminophosphonates has been developed taking advantage of the tert-butyldimethylsilyl triflate activated addition of diethylphosphite to N-benzylnitrones derived from chiral α-alkoxy and α-(Boc-amino) aldehydes. The stereoselective carbon− phosphorus bond-forming reaction proceeded smoothly to give α-(hydroxyamino)phosphonate intermediates as the primary
A General Method for the Vinylation of Nitrones. Synthesis of Allyl Hydroxylamines and Allyl Amines
作者:Pedro Merino、Sonia Anoro、Santiago Franco、Jose M. Gascon、Victor Martin、Francisco L. Merchan、Julia Revuelta、Tomas Tejero、Victoria Tuñon
DOI:10.1080/00397910008087449
日期:2000.8
An examination of the vinylation of several nitrones is presented. Whereas a complete diastereofacial discrimination was observed upon the addition of vinyl organometallic reagents to alpha-alkoxy nitrones, the same reaction with alpha-amino nitrones pave syn adducts in all cases, with the only exception of a L-serine-derived alpha-amino monoprotected nitrone. The obtained allyl hydroxylamines were easily transformed into synthetically valuable allyl amines.