Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to para-Quinone Methides

The isothiourea-catalyzed enantioselective 1,6-conjugate addition of para-nitrophenyl esters to 2,6-disubstituted para-quinone methides is reported. para-Nitrophenoxide, generated in situ from initial N-acylation of the isot...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Jude N. Arokianathar, Will C. Hartley, Calum McLaughlin, Mark D. Greenhalgh, Darren Stead, Sean Ng, Alexandra M. Z. Slawin, Andrew D. Smith
Formato:	article
Lenguaje:	EN
Publicado:	MDPI AG 2021
Materias:	isothiourea ammonium enolate aryloxide quinone methide ester functionalization 1,6-conjugate addition Organic chemistry QD241-441
Acceso en línea:	https://doaj.org/article/355f0306f6ad4c5f949bcd0c0470370b
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:355f0306f6ad4c5f949bcd0c0470370b
record_format	dspace
spelling	oai:doaj.org-article:355f0306f6ad4c5f949bcd0c0470370b2021-11-11T18:22:01ZIsothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides10.3390/molecules262163331420-3049https://doaj.org/article/355f0306f6ad4c5f949bcd0c0470370b2021-10-01T00:00:00Zhttps://www.mdpi.com/1420-3049/26/21/6333https://doaj.org/toc/1420-3049The isothiourea-catalyzed enantioselective 1,6-conjugate addition of <i>para</i>-nitrophenyl esters to 2,6-disubstituted <i>para</i>-quinone methides is reported. <i>para</i>-Nitrophenoxide, generated in situ from initial <i>N</i>-acylation of the isothiourea by the <i>para</i>-nitrophenyl ester, is proposed to facilitate catalyst turnover in this transformation. A range of <i>para</i>-nitrophenyl ester products can be isolated, or derivatized in situ by addition of benzylamine to give amides at up to 99% yield. Although low diastereocontrol is observed, the diastereoisomeric ester products are separable and formed with high enantiocontrol (up to 94:6 er).Jude N. ArokianatharWill C. HartleyCalum McLaughlinMark D. GreenhalghDarren SteadSean NgAlexandra M. Z. SlawinAndrew D. SmithMDPI AGarticleisothioureaammonium enolatearyloxidequinone methideester functionalization1,6-conjugate additionOrganic chemistryQD241-441ENMolecules, Vol 26, Iss 6333, p 6333 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	isothiourea ammonium enolate aryloxide quinone methide ester functionalization 1,6-conjugate addition Organic chemistry QD241-441
spellingShingle	isothiourea ammonium enolate aryloxide quinone methide ester functionalization 1,6-conjugate addition Organic chemistry QD241-441 Jude N. Arokianathar Will C. Hartley Calum McLaughlin Mark D. Greenhalgh Darren Stead Sean Ng Alexandra M. Z. Slawin Andrew D. Smith Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
description	The isothiourea-catalyzed enantioselective 1,6-conjugate addition of <i>para</i>-nitrophenyl esters to 2,6-disubstituted <i>para</i>-quinone methides is reported. <i>para</i>-Nitrophenoxide, generated in situ from initial <i>N</i>-acylation of the isothiourea by the <i>para</i>-nitrophenyl ester, is proposed to facilitate catalyst turnover in this transformation. A range of <i>para</i>-nitrophenyl ester products can be isolated, or derivatized in situ by addition of benzylamine to give amides at up to 99% yield. Although low diastereocontrol is observed, the diastereoisomeric ester products are separable and formed with high enantiocontrol (up to 94:6 er).
format	article
author	Jude N. Arokianathar Will C. Hartley Calum McLaughlin Mark D. Greenhalgh Darren Stead Sean Ng Alexandra M. Z. Slawin Andrew D. Smith
author_facet	Jude N. Arokianathar Will C. Hartley Calum McLaughlin Mark D. Greenhalgh Darren Stead Sean Ng Alexandra M. Z. Slawin Andrew D. Smith
author_sort	Jude N. Arokianathar
title	Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
title_short	Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
title_full	Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
title_fullStr	Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
title_full_unstemmed	Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides
title_sort	isothiourea-catalyzed enantioselective α-alkylation of esters via 1,6-conjugate addition to <i>para</i>-quinone methides
publisher	MDPI AG
publishDate	2021
url	https://doaj.org/article/355f0306f6ad4c5f949bcd0c0470370b
work_keys_str_mv	AT judenarokianathar isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT willchartley isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT calummclaughlin isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT markdgreenhalgh isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT darrenstead isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT seanng isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT alexandramzslawin isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides AT andrewdsmith isothioureacatalyzedenantioselectiveaalkylationofestersvia16conjugateadditiontoiparaiquinonemethides
_version_	1718431815761395712

Isothiourea-Catalyzed Enantioselective α-Alkylation of Esters via 1,6-Conjugate Addition to <i>para</i>-Quinone Methides

Ejemplares similares