Isatoicanhydride (1) can be attached to Merrifield resin by alkylation on its nitrogen. A maximum loading of 3.2 mmol of anhydride/g of 5 was achieved. This resin, due to the highly reactive anhydride moiety, completely removes primary and secondary aliphatic amines from reactions where they are used in excess.
An efficient, mild, and environmentally friendly route has been developed for the synthesis of unsymmetrical thiourea derivatives in moderate yields by the reaction of tertiary aromatic and aliphatic amines with phenyl-iso-thiocyanate in the presence of N-ZnO as a photocatalyst under visible-light irradiation. This method provides a pathway to activate the tertiary aromatic and aliphatic amines via
Cycloaddition Chemistry of 1,3-Thiazolium-4-olate Systems. Reaction with Nitroalkenes and Interpretation of Results Using PM3 Calculations
作者:Martín Avalos、Reyes Babiano、Andrés Cabanillas、Pedro Cintas、Francisco J. Higes、José L. Jiménez、Juan C. Palacios
DOI:10.1021/jo952275g
日期:1996.1.1
room temperature in methylene chloride (48 h) resulted in two readily separable diastereomeric racemic 4,5-dihydrothiophenes via transient cycloadducts that underwent rearrangement under these reaction conditions. Using chiral carbohydrate-derived nitroalkenes, twodiastereomeric dihydrothiophenes were obtained, showing that regiospecificity and facial selectivity were involved in these cycloadditions