Synthesis and stability of new spiroaminoborate esters
摘要:
New spiroaminoborate esters derived from 1,1-diphenylprolinol, ephedrine, and dihydroquinine with different alkoxy substituents were prepared as stable crystalline compounds and characterized by spectroscopical analysis and specific rotation. The structure of the spiroborate 4 derived from 1,1-diphenylprolinol and dicyclohexyl-1,1'-diol was confirmed by X-ray analysis. (C) 2011 Elsevier Ltd. All rights reserved.
Convenient Synthesis of Ethenylcyclopropane and Some 2-Cyclopropylcyclopropane Derivatives¹
作者:Armin de Meijere、Valentin Rassadin、Viktor Sokolov、Alexander Khlebnikov、Nikolay Ulin、Sergei Kozhushkov
DOI:10.1055/s-0031-1289600
日期:2012.2
diazoacetate gave ethyl 2-cyclopropylcyclopropanecarboxylate (cis/trans-9, ratio 1:1.4) in 80% yield. The latter was also prepared in 79% overall yield by sequential cyclopropanation of buta-1,3-diene with ethyl diazoacetate [under Rh2(OAc)4 catalysis] and diiodomethane/diethylzinc/trifluoroacetic acid. Curtius degradation of 2-cyclopropylcyclopropanecarboxylic acid (obtained by hydrolysis of the ester) gave
Enantioselective Reduction of Ketones and Synthesis of 2-Methyl-2,3-dihydro-1-benzofuran Catalyzed by Chiral Spiroborate Ester
作者:H. S. Patil、M. D. Nikalje、A. U. Chopade、M. U. Chopade
DOI:10.1134/s1070428021040163
日期:2021.4
achieved through the use of chiral spiroborate ester catalyst. The catalyst is applicable for both analytical and industrial purposes since it is not sensitive to air and moisture. A rapid synthetic route has been developed for the preparation of (S)-2-methyl-2,3-dihydro-1-benzofuran via enantioselective reduction of homobenzylic ketone in the presence of a chiral spiroborate catalyst as the key step.
Synthesis of Spiroborate Esters from 1,2-Aminoalcohols, Ethylene Glycol and Triisopropyl Borate: Preparation of (<i>S</i>)-1-(1,3,2-Dioxaborolan-2-yloxy)-3-Methyl-1,1-Diphenylbutan-2-Amine
Kuznetsov, Russian Journal of General Chemistry, 2000, vol. 70, # 10, p. 1576 - 1580
作者:Kuznetsov
DOI:——
日期:——
Synthesis and stability of new spiroaminoborate esters
作者:Viatcheslav Stepanenko、Melvin de Jesús、Carmelo Garcia、Charles L. Barnes、Margarita Ortiz-Marciales
DOI:10.1016/j.tetlet.2011.12.054
日期:2012.2
New spiroaminoborate esters derived from 1,1-diphenylprolinol, ephedrine, and dihydroquinine with different alkoxy substituents were prepared as stable crystalline compounds and characterized by spectroscopical analysis and specific rotation. The structure of the spiroborate 4 derived from 1,1-diphenylprolinol and dicyclohexyl-1,1'-diol was confirmed by X-ray analysis. (C) 2011 Elsevier Ltd. All rights reserved.