A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration
Autor(a) principal: | |
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Data de Publicação: | 2015 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10174/16623 https://doi.org/10.1039/c5ra19599c |
Resumo: | We report a new synthetic method for the synthesis of a family of dibenzodiazepines (DBDAs), employing Pd-catalyzed C-N coupling of o-bromoaldimine, with o-bromoaniline as the key step. Eleven DBDAs were prepared, containing electron-withdrawing groups (CN, F, NO2) and electron-donating groups (OMe). The reaction conditions were optimized (catalyst, phosphine, base and solvent) and best results were obtained with Pd(OAc)(2), SPhos, Cs2CO3 in THF. Due to the ambiguity of the mechanism at hand, various mechanistic studies were performed, that included DFT calculations. The oxidative addition process was studied in detail by DFT, and these studies supported the observed reaction regioselectivity. The adducts formed between the aldimine and the Pd(0) catalyst were calculated to be more stable than the ones formed with the amine, and the barrier for the oxidative addition at the C-Br bond of the aldimine was calculated to be lower than the one at the C-Br bond of the aryl amine. The formation of DBDA over the dibenzoaminopiperidine has been explained in the final cyclization step. |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic considerationCatálisemedicinaWe report a new synthetic method for the synthesis of a family of dibenzodiazepines (DBDAs), employing Pd-catalyzed C-N coupling of o-bromoaldimine, with o-bromoaniline as the key step. Eleven DBDAs were prepared, containing electron-withdrawing groups (CN, F, NO2) and electron-donating groups (OMe). The reaction conditions were optimized (catalyst, phosphine, base and solvent) and best results were obtained with Pd(OAc)(2), SPhos, Cs2CO3 in THF. Due to the ambiguity of the mechanism at hand, various mechanistic studies were performed, that included DFT calculations. The oxidative addition process was studied in detail by DFT, and these studies supported the observed reaction regioselectivity. The adducts formed between the aldimine and the Pd(0) catalyst were calculated to be more stable than the ones formed with the amine, and the barrier for the oxidative addition at the C-Br bond of the aldimine was calculated to be lower than the one at the C-Br bond of the aryl amine. The formation of DBDA over the dibenzoaminopiperidine has been explained in the final cyclization step.RSC2016-01-13T17:45:12Z2016-01-132015-11-05T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10174/16623http://hdl.handle.net/10174/16623https://doi.org/10.1039/c5ra19599ceng99990-999992046-2069WOS:0003654068000505RSC Advancesajb@uevora.ptcarolsmarq@gmail.comdanielaaspeixoto@gmail.comabellocati@hotmail.comgoth.uc@sapo.ptJoão Paulo Ramalho310Burke, AnthonyMarques, CAROLINAPeixoto, DanielaLocati, AbelGoth, AlbertinoRamalho, João Pauloinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-08-08T04:16:50ZPortal AgregadorONG |
dc.title.none.fl_str_mv |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
title |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
spellingShingle |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration Burke, Anthony Catálise medicina |
title_short |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
title_full |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
title_fullStr |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
title_full_unstemmed |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
title_sort |
A catalytic route to dibenzodiazepines involving Buchwald-Hartwig coupling: reaction scope and mechanistic consideration |
author |
Burke, Anthony |
author_facet |
Burke, Anthony Marques, CAROLINA Peixoto, Daniela Locati, Abel Goth, Albertino Ramalho, João Paulo |
author_role |
author |
author2 |
Marques, CAROLINA Peixoto, Daniela Locati, Abel Goth, Albertino Ramalho, João Paulo |
author2_role |
author author author author author |
dc.contributor.author.fl_str_mv |
Burke, Anthony Marques, CAROLINA Peixoto, Daniela Locati, Abel Goth, Albertino Ramalho, João Paulo |
dc.subject.por.fl_str_mv |
Catálise medicina |
topic |
Catálise medicina |
description |
We report a new synthetic method for the synthesis of a family of dibenzodiazepines (DBDAs), employing Pd-catalyzed C-N coupling of o-bromoaldimine, with o-bromoaniline as the key step. Eleven DBDAs were prepared, containing electron-withdrawing groups (CN, F, NO2) and electron-donating groups (OMe). The reaction conditions were optimized (catalyst, phosphine, base and solvent) and best results were obtained with Pd(OAc)(2), SPhos, Cs2CO3 in THF. Due to the ambiguity of the mechanism at hand, various mechanistic studies were performed, that included DFT calculations. The oxidative addition process was studied in detail by DFT, and these studies supported the observed reaction regioselectivity. The adducts formed between the aldimine and the Pd(0) catalyst were calculated to be more stable than the ones formed with the amine, and the barrier for the oxidative addition at the C-Br bond of the aldimine was calculated to be lower than the one at the C-Br bond of the aryl amine. The formation of DBDA over the dibenzoaminopiperidine has been explained in the final cyclization step. |
publishDate |
2015 |
dc.date.none.fl_str_mv |
2015-11-05T00:00:00Z 2016-01-13T17:45:12Z 2016-01-13 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10174/16623 http://hdl.handle.net/10174/16623 https://doi.org/10.1039/c5ra19599c |
url |
http://hdl.handle.net/10174/16623 https://doi.org/10.1039/c5ra19599c |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
99990-99999 2046-2069 WOS:000365406800050 5 RSC Advances ajb@uevora.pt carolsmarq@gmail.com danielaaspeixoto@gmail.com abellocati@hotmail.com goth.uc@sapo.pt João Paulo Ramalho 310 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
RSC |
publisher.none.fl_str_mv |
RSC |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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repository.mail.fl_str_mv |
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_version_ |
1777304614640549888 |