Direct ionic liquid promoted organocatalyzed diazo-transfer reactions: diversity-oriented synthesis of diazo-compounds
作者:Dhevalapally B. Ramachary、Vidadala V. Narayana、Kinthada Ramakumar
DOI:10.1016/j.tetlet.2008.02.159
日期:2008.4
A practical and novel ionic liquid promoted organocatalytic selective diazo-transfer process for the synthesis of highly substituted diazo-compounds in high yields is reported. The ionic liquid can be reused without affecting the reaction rates or yields over five runs.
from 1,3-disubstituted barbituric acids to biologicallyrelevant oxazolo[5,4-d]pyrimidine-5,7-diones was developed that features sulfonyl-azide-free (SAFE) diazo transfer and Rh2(esp)2-catalyzed cycloaddition of the resulting 5-diazobarbituric acids with aliphatic and aromatic nitriles. Besides being shorter compared to the previously described approaches, the method allows introduction of alkyl substituents
从1,3-二取代的巴比妥酸到生物学上相关的恶唑并[5,4- d ]嘧啶-5,7-二酮的另一种途径被开发出来,其特征在于无磺酰叠氮(SAFE)的重氮转移和Rh 2(esp)2催化的5-重氮巴比妥酸与脂族和芳族腈的环加成反应。除了比先前描述的方法短之外,该方法还允许在稠合杂环系统的1,3-恶唑环上引入烷基取代基。
Dichlorination of α-Diazo-β-dicarbonyls Using (Dichloroiodo)benzene
作者:Graham Murphy、Keith Coffey
DOI:10.1055/s-0034-1380304
日期:2015.5
α-Diazo-β-dicarbonyl compounds were chlorinated using (dichloro)iodobenzene and an activating catalyst. A broad range of reaction rates was observed, which paralleled the relative stability/nucleophilicity of the diazo compounds. Acyclic diazocarbonyls reacted faster than cyclics, and β-diketones were much faster to react than β-keto esters or β-diesters. Lewis acid activation was used for the first
A ‘sulfonyl-azide-free’ (SAFE) aqueous-phase diazo transfer reaction for parallel and diversity-oriented synthesis
作者:Dmitry Dar’in、Grigory Kantin、Mikhail Krasavin
DOI:10.1039/c9cc02042j
日期:——
Diazotransferreactions are notoriously associated with the use of potentially explosive sulfonyl azides. The first ‘sulfonyl-azide-free’ (SAFE) protocol for producing diazo compounds from their active-methylene precursors via the Regitz diazotransferreaction was developed and has displayed a remarkable substrate scope. It can be applied to generating arrays of diazo compounds for further evolution
The paper describes synthesis of a novel ionic liquid-supported sulfonyl azide and its applications as diazotransfer reagent of active methylene compounds as well as deformylative diazo transfer reagent. The diazo compounds were isolated in excellent yields (82–94%) and high purity. The method offers better separation of product and reagent. This method is experimentally simple and mild, and requires