Regio- and Diastereoselective Access to 4-Imidazolidinones via an Aza-Mannich Initiated Cyclization of Sulfamate-Derived Cyclic Imines with α-Halo Hydroxamates
An efficient regio- and diastereoselective cyclization of sulfamate-derived cyclic imines with unsubstituted or monosubstituted α-halo hydroxamates is developed under mild conditions. This reaction proceeds smoothly under transition-metal-free conditions via a domino aza-Mannich addition/intramolecular nucleophilic substitution sequence, providing a convenient route to access 2-monosubstituted and
with NBS in toluene was found to conveniently afford the corresponding carboxylicesters, including those bearing a bulky or long-chain substituent, in satisfactory to excellent yields. This approach not only represents a convenient and economic approach to a direct transformation of an alkoxyamide moiety into the carboxylicester functional group, via oxidative homocoupling and the subsequent thermal
Synthesis of spirobarbiturate-pyrrolidinones <i>via</i> a domino aza-Michael/S<sub>N</sub>2 cyclization of barbiturate-derived alkenes with <i>N</i>-alkoxy α-haloamides
A highly efficient domino aza-MIRC (Michael Induced RingClosure) reaction between barbiturate-derived alkenes and N-alkoxy α-haloamides has been achieved in moderate to excellent yields. This reaction proceeds smoothly under mild conditions via a domino aza-Michael addition/intramolecular SN2 sequence, providing a practical tool in the synthesis of bioactive molecules spirobarbiturate-3-pyrrolidinones
The convenient preparation of N2-unprotected five-membered cyclic guanidines was achieved through a cascade [3 + 2] cycloaddition between organo-cyanamides and α-haloamides under mild conditions in good to excellent yields (up to 99%). The corresponding cyclic guanidines could be easily transformed into hydantoins via hydrolysis.
Facile synthesis of 1,2,4,5-tetrahydro-1,4-benzodiazepin-3-ones <i>via</i> cyclization of <i>N</i>-alkoxy α-halogenoacetamides with <i>N</i>-(2-chloromethyl)aryl amides
作者:Qiaomei Jin、Dongjian Zhang、Jian Zhang
DOI:10.1039/c9ob02260k
日期:——
A facile and efficient cyclization of N-alkoxy α-halogenoacetamides with N-(2-chloromethyl)aryl amides has been achieved for rapid access to 1,2,4,5-tetrahydro-1,4-benzodiazepine-3-one derivatives (up to 95% yield). The intriguing features of this intermolecular cyclization include its mild reaction conditions and easy handling for scalable synthesis.