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1.
J Am Chem Soc ; 146(17): 12053-12062, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38622809

RESUMO

Three-component diene carboaminations offer a potent means to access synthetically valuable allylic amines with rapid molecular complexity escalation. The existing literature primarily discloses racemic examples, necessitating the use of halides/pseudohalides as substrates. This paper introduces a photoinduced Pd-catalyzed enantioselective three-component carboamination of aryl-substituted 1,3-dienes, leveraging aliphatic C-H bonds for rapid synthesis. The reaction employs 10 mol % of chiral palladium catalyst and an excess aryl bromide as the HAT reagent. This approach yields diverse chiral allylamines with moderate to excellent enantioselectivities. Notably, it stands as the first instance of an asymmetric three-component diene carboamination reaction, directly utilizing abundant C(sp3)-H bearing partners, such as toluene-type substrates, ethers, amines, esters, and ketones. The protocol exhibits versatility across amines, encompassing aliphatic, aromatic, primary, and secondary derivatives. This method could serve as a versatile platform for stereoselective incorporation of various nucleophiles, dienes, and C(sp3)-H bearing partners.

2.
Chemistry ; 28(11): e202104218, 2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35043467

RESUMO

A Pd-catalyzed cascade C-H functionalization/asymmetric allylation reaction with aryl α-diazoamides and allenes has been developed. The reaction provides an efficient approach to construct chiral 3,3-disubstituted oxindole derivatives in high levels of yield and enantioselectivity (up to 93 % ee). Notably, the chromium complex works as Lewis acid to facilitate the formation of palladium carbene and to enhance acidity of carboxylic acid, allowing for higher stereochemical control and efficiency.


Assuntos
Alcadienos , Paládio , Catálise , Ácidos de Lewis
3.
Zhong Yao Cai ; 34(3): 392-5, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21823457

RESUMO

OBJECTIVE: The chemical components of essential oil from Anaphalis aureopunctata were analyzed by GC-MS. METHODS: Essential oil was extracted by stem distillation (SD). The chemical components of essential oil were analyzed by GC-MS. RESULTS: The main components in the oil were Eudesma-4(14), 11-diene, alpha-Bisabolol,6,10,14-trimethyl- 2-Pentadecanone,Caryophyllene oxide,alpha-Selinene and so on. CONCLUSION: This is the first time to adopt GC-MS to analyze the chemical components of volatile oil of Anaphalis au-reopunctata, and this study can provide science basis for further research development of Anaphalis aureopunctata.


Assuntos
Asteraceae/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/química , Plantas Medicinais/química , Sesquiterpenos/análise , Ésteres/análise , Ácidos Graxos Insaturados/análise , Óleos Voláteis/isolamento & purificação , Sesquiterpenos de Eudesmano , Tetra-Hidronaftalenos/análise
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