326598-60-1Relevant academic research and scientific papers
AgNO3Catalyzed Regio-Selective Synthesis of 3-Alkyl/Aryl-idene-3,4-dihydro-4-tosyl-2H-1,4-Benzoxazine: Novel Anti-Tubercular Scaffolds
Karunanidhi, Sivanandhan,Karpoormath, Rajshekhar,Bera, Milan,Rane, Rajesh A.,Palkar, Mahesh B.
, p. 1611 - 1616 (2016/09/23)
A facile and efficient method for the construction of 3-alkyl/aryl substituted 1,4-benzoxazine and benzoxazepine via AgNO3catalyzed cyclization of propargyloxy sulfonamides and their anti-tubercular activity against Mycobacterium tuberculosis H37RVis described. This cyclization proceeds through 6-exo-dig manner to generate the products in moderate to good yields.
A palladium-catalyzed facile and general method for the stereoselective synthesis of (E)-3-arylidene-3,4-dihydro-2H-1,4-benzoxazines and their naphthoxazine analogues
Brahma, Kaushik,Das, Bimolendu,Chowdhury, Chinmay
, p. 5863 - 5871 (2015/03/30)
Palladium-catalyzed cyclocondensation of an aryl iodide with N-tosyl-2-(prop-2′-ynyloxy)aniline at room temperature is shown to constitute a convenient general method for the synthesis of (E)-3-arylidene-3,4-dihydro-2H-1,4-benzoxazines in moderate to very good yields. The method could also be extended to the synthesis of (E)-3-arylidene-2H-naphth[1,2-b][1,4]oxazines. The regio- and stereo-selectivity of the process, short reaction time, operational simplicity, and use of inexpensive starting materials represent its attractive features.
Totally regio- and stereoselective synthesis of (E)-3-arylidene-3,4-dihydro-2H-1,4-benzoxazines under palladium catalyst
Chowdhury, Chinmay,Brahma, Kaushik,Mukherjee, Sanjukta,Sasmal, Anup Kumar
supporting information; experimental part, p. 2859 - 2861 (2010/07/06)
A new, one-pot palladium catalyzed reaction has been developed for the general synthesis of (E)-3-arylidene-3,4-dihydro-2H-1,4-benzoxazines at room temperature. The reaction procedure tolerates various functional groups. The method is characterized by reg
Palladium-catalyzed heteroannulation leading to heterocyclic structures with two heteroatoms: A highly regio- and stereoselective synthesis of (Z)-4-alkyl-2-alkyl(aryl)idene-3,4-dihydro-2H-1,4,-benzoxazines and (Z)-3-alkyl(aryl)idene-4-tosyl-3,4-dihydro-2H-1,4-benzoxazines
Kundu,Chaudhuri,Upadhyay
, p. 20 - 29 (2007/10/03)
A highly convenient method has been developed for the synthesis of (Z)-4-alkyl-2-alkyl(aryl)idene-3,4-dihydro-2H-1,4-benzoxazines 9 and (Z)-3-alkyl(aryl)idene-4-tosyl-3,4-dihydro-2H-1,4-benzoxazines 34-38 through palladium - copper-catalyzed reactions. Aryl halides 7 reacted with 2-[Nalkyl(benzyl)-N-prop-2′-ynyl]aminophenyl tosylate 6 in the presence of (PPh3)2PdCl2 (3 mol %), CuI(5 mol %) in triethylamine at room temperature to yield 2-[N-alkyl(benzyl)-N-(3-aryl-prop-2′-ynyl)]aminophenyl tosylates 8 in extremely good yields (72-96%). The latter could then be cyclized with KOH in ethanol - water to Z-9 in a highly regio- and stereoselective manner. Similarly, palladium copper-catalyzed reaction of 2-(prop-2′-ynyloxy)aniline (21) with aryl iodides 7 led to 22-26 which after tosylation and cyclization with cuprous iodide in CH3CN in the presence of K2CO3 and Bu4-NBr led to the (Z)-3-alkyl(aryl)idene-4-tosyl 3,4-dihydro-2H-1,4-benzoxazines 34-38 in good overall yields. The Z-stereochemistry of the products was established from 1H NMR spectra, 3JCH values (between vinylic proton and methylenic carbon of the heterocyclic ring), NOE experiments, and X-ray analysis· The method was also found to be suitable for the synthesis of bis(benzoxazinylated) derivatives 17, 39, and 2-alkyl-3,4-dihydro-2H-1,4-benzoxazines 18. Our method for the synthesis of 3,4-dihydro-2H-1,4-benzoxazines is highly efficacious, using easily available starting materials under very mild conditions. Also the synthesis of some novel 5-substituted uracil derivatives 40 and 41 containing the benzoxazinyl moiety and of potential biological interest is being reported.
