dichloride promoted the successful cyclodesulfurization of thioureas with short reaction times under mild reaction conditions. This reaction is the first example of the synthesis of heterocyclic rings using a pentavalent organobismuth reagent.
P(III)‐Mediated Cascade C‐N/C‐S Bond Formation: A Protocol towards the Synthesis of
<i>N</i>
,
<i>S</i>
‐Heterocycles and Spiro Compounds
作者:Saibabu Polina、V. P. Rama Kishore Putta、Raghuram Gujjarappa、Virender Singh、Prasad Pralhad Pujar、Chandi C. Malakar
DOI:10.1002/adsc.202001149
日期:2021.1.19
of C−N/C−S bond has been devised. The developed heterocyclization method was exercised for the synthesis of a diverse range of N,S‐heterocycles and related spiro molecules. P(NMe2)3 revealed the maximum efficacies under the aerobic reaction conditions and a spectrum of bis‐nucleophiles, and isothiocyanates were tolerated well to serve the access of manifold immense molecules.
A facile and environmentally benign access to N-aryl/alkyl-4H-benzoxazin-2-amines is achieved from 1-[2-(hydroxymethyl)phenyl/alkyl]-3-phenylthioureas under transition-metal-free conditions. The conversions occur smoothly in the presence of a catalytic amount of molecular iodine and hydrogen peroxide as the oxidant in tetrahydrofuran at room temperature to afford moderate to good yields (28–90%) of