Facile direct synthesis of unsymmetrical ureas from N-Alloc-, N-Cbz-, and N-Boc-protected amines using DABAL-Me3
作者:Soosung Kang、Hee-Kwon Kim
DOI:10.1016/j.tet.2018.06.011
日期:2018.7
A practical synthetic method for the direct synthesis of unsymmetrically substituted ureas from N-Alloc-, N-Cbz-, and N-Boc-protected amines is described. In this study, efficient direct conversion of the Alloc-, Cbz-, and Boc-carbamate compounds to ureas was achieved in the presence of DABAL-Me3, an air stable and easily handled reagent. Using this reaction method, both protected aromatic and aliphatic
A Facile and Efficient Method for the Formation of Unsymmetrical Ureas Using DABAL-Me3
作者:Byung-Hoon Jeong、Hee-Kwon Kim、David H. Thompson
DOI:10.1071/ch15675
日期:——
A practical synthetic method for the formation of unsymmetrical-substituted ureas is described. The synthesis of the unsymmetrical ureas was readily performed from 2,2,2-trichloroethyl carbamate compounds by treatment of amines with bis(trimethylaluminum)-1,4-diazabicyclo[2.2.2]octane (DABAL-Me3). Using this reaction protocol, various trisubstituted and tetrasubstituted ureas were synthesized in high
A Facile Method for the Preparation of Unsymmetrical Ureas Utilizing Zirconium(IV) Chloride
作者:Anna Lee、Hee-Kwon Kim、David H. Thompson
DOI:10.1002/bkcs.10646
日期:2016.2
ureas from amines is described. Carbamoyl imidazole compounds were prepared by the reaction of 1,1‐carbonyldiimidazole with primary or secondary amines, and further activation by treatment with zirconium(IV) chloride to generate the desired urea. This reaction protocol was applied to the synthesis of tri and tetrasubstituted ureas with high yields. This study provides an alternative guideline for the