3(Z)-Benzoylmethylidene-6-nitro-3,4-dihydro-2H-1,4-benzooxazin-2-one reacts with (COCl)(2) as imino enol rather than enamino ketone. The reaction is accompanied by replacement of the hydroxy group by chlorine. The molecular and crystal structures of the starting 1,4-benzooxazin-2-one and its chlorinated derivative were studied by X-ray diffraction analysis.
“On water” ultrasound-assisted one pot efficient synthesis of functionalized 2-oxo-benzo[1,4]oxazines: First application to the synthesis of anticancer indole alkaloid, Cephalandole A
作者:Pradeep K. Jaiswal、Vashundhra Sharma、Jaroslav Prikhodko、Irina V. Mashevskaya、Sandeep Chaudhary
DOI:10.1016/j.tetlet.2017.03.048
日期:2017.5
For the first time, an efficient, simple, synthetic green protocol for the one-pot synthesis of functionalized 2-oxo-benzo[1,4]oxazines 24–29 in water under ultrasound irradiation is presented. As compared to conventional methods, the present protocol avoids traditional chromatography and purification steps and furnished the target molecules in excellent yields (upto 98%) with no side products. The