Relevant articles and documents
All total 62 Articles be found
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La Forge et al.
, p. 391 (1952)
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Clusius,Luehti
, p. 445 (1957)
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A pilot-scale synthesis of (1R)-trans-2-(2,3-dihydro-4-benzofuranyl) cyclopropanecarboxylic acid: A practical application of asymmetric cyclopropanation using a styrene as a limiting reagent
Simpson, James H.,Godfrey, Jollie,Fox, Rita,Kotnis, Atul,Kacsur, David,Hamm, Jason,Totelben, Michael,Rosso, Victor,Mueller, Richard,Delaney, Edward,Deshpande, Rajendra P.
, p. 3569 - 3574 (2003)
Asymmetric cyclopropanation of styrene 1 (as the limiting reagent) was demonstrated using excess ethyl diazoacetate and catalytic Ru(ip-Pybox). Selective hydrolysis of the resulting 90:10 trans:cis mixture of cyclopropane 4 generated cyclopropyl acid 2 as a 96:4 trans:cis mixture with 84% e.e. for the trans-cyclopropane. Further purification and enantiomeric enrichment was achieved by diastereoselective crystallization with (+)-dehydroabeitylamine to afford the (R,R)-isomer with ≥99.9% e.e in 60-65 M% yield starting from styrene 1.
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Womack,Nelson
, p. 392 (1955)
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METHOD OF PRODUCING NITRO COMPOUND
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Paragraph 0041, (2021/06/25)
PROBLEM TO BE SOLVED: To provide a production method which can efficiently provide a nitro compound in an industrial scale. SOLUTION: A method of producing a compound represented by formula (2) comprises using nitric acid to nitrate a compound represented by formula (1) in the presence of concentrated sulfuric acid that weighs 1.5-5.0 times more than the compound represented by formula (1). [In formulas (1) and (2), X1 and X2 are identical or different and represent halogen atoms, and R represents an optionally substituted 6-membered heterocyclic group.] SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
B(C6F5)3-Catalyzed site-selective N1-alkylation of benzotriazoles with diazoalkanes
Guo, Jing,Mandal, Dipendu,Stephan, Douglas W.,Wu, Yile,Zhao, Yunbo
supporting information, p. 7758 - 7761 (2021/08/13)
Alkylation of benzotriazoles is synthetically challenging, often leading to mixtures of N1 and N2 alkylation. Herein, metal-free catalytic site-selective N1-alkylation of benzotriazoles with diazoalkanes is described in the presence of 10 mol% of B(C6F5)3. These reactions provide N1-alkylated benzotriazoles in good to excellent yields and this protocol is successfully adapted to gram-scale syntheses as well as a derivative with antimicrobial activity.