A Novel, One-pot Synthesis of 2H-Benz[e]-1,3-oxazine-2-thiones†

Abstract

A novel, acid-catalysed cyclisation of salicylaldehyde thiosemicarbazones (1a±d) yields new 2H-benz[e]-1,3-oxazine-2thiones (2a±d) in a one-pot procedure.

Novel Salicylaldehyde-Based Mineral-Supported Expeditious Synthesis of Benzoxazin-2-ones

“…Interestingly, this is the first example of the synthesis of 4-hydrazinobenzoxazinones 9 and their reductive dehydrazination to 10 . The key element in our approach is the novel utilization of salicylaldehyde as a bifunctional building block whose application to the construction of various benzo-fused oxygen heterocycles of chemical and biological interest is well documented. − …”

One-Pot Annulation of Pyrimidine Ring on Azoles Under Microwave Irradiation and Solvent-Free Conditions

“…Prompted by the above reports and in pursuing our work on new cyclization methods, [9][10][11] we have devised an expeditious and highly diastereoselective one-pot annulation of pyrimidine ring on azoles to give 4 using microwaves in catalyst-and solvent-free conditions (Scheme 1).…”