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1.
Angew Chem Int Ed Engl ; 56(21): 5806-5811, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28418118

RESUMO

A mild, asymmetric Heck-Matsuda reaction of five-, six- and seven-membered ring alkenes and aryl diazonium salts is presented. High yields and enantioselectivities were achieved using Pd0 and chiral anion co-catalysts, the latter functioning as a chiral anion phase-transfer (CAPT) reagent. For certain substrate classes, the chiral anion catalysts were modulated to minimize the formation of undesired by-products. More specifically, BINAM-derived phosphoric acid catalysts were shown to prevent alkene isomerization in cyclopentene and cycloheptene starting materials. DFT(B3LYP-D3) computations revealed that increased product selectivity resulted from a chiral anion dependent lowering of the activation barrier for the desired pathway.


Assuntos
Compostos de Diazônio/química , Ânions , Catálise , Cicloexenos/química , Estrutura Molecular , Transição de Fase , Fenol/química , Estereoisomerismo
2.
Angew Chem Int Ed Engl ; 53(22): 5600-3, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24715416

RESUMO

Herein is reported the first asymmetric utilization of aryldiazonium cations as a source of electrophilic nitrogen. This is achieved through a chiral anion phase-transfer pyrroloindolinization reaction that forms C3-diazenated pyrroloindolines from simple tryptamines and aryldiazonium tetrafluoroborates. The title compounds are obtained in up to 99% yield and 96% ee. The air- and water-tolerant reaction allows electronic and steric diversity of the aryldiazonium electrophile and the tryptamine core.


Assuntos
Indóis/química , Pirróis/química , Ânions/química , Catálise , Cátions/química , Ciclização , Compostos de Diazônio/química , Indóis/síntese química , Estereoisomerismo , Triptaminas/química
3.
Appl Clin Inform ; 14(5): 944-950, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37802122

RESUMO

Precise, reliable, valid metrics that are cost-effective and require reasonable implementation time and effort are needed to drive electronic health record (EHR) improvements and decrease EHR burden. Differences exist between research and vendor definitions of metrics. PROCESS: We convened three stakeholder groups (health system informatics leaders, EHR vendor representatives, and researchers) in a virtual workshop series to achieve consensus on barriers, solutions, and next steps to implementing the core EHR use metrics in ambulatory care. CONCLUSION: Actionable solutions identified to address core categories of EHR metric implementation challenges include: (1) maintaining broad stakeholder engagement, (2) reaching agreement on standardized measure definitions across vendors, (3) integrating clinician perspectives, and (4) addressing cognitive and EHR burden. Building upon the momentum of this workshop's outputs offers promise for overcoming barriers to implementing EHR use metrics.


Assuntos
Registros Eletrônicos de Saúde , Informática Médica , Humanos , Assistência Ambulatorial , Benchmarking , Consenso
4.
J Org Chem ; 75(23): 8330-2, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21047088

RESUMO

A mild Negishi cross-coupling of 2-heterocyclic organozinc reagents and aryl chlorides is described. The use of Pd(2)(dba)(3) and X-Phos as a ligand provides high yields for many examples. An efficient method to generate the organozinc reagents at room temperature is also demonstrated.


Assuntos
Hidrocarbonetos Clorados/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Reagentes de Ligações Cruzadas , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Estrutura Molecular
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