Objective: Many methods can be found in literature for the synthesis a Oxazines and Thiazines. Few are reported one-pot multi component cyclo-condensation of an alkayane urea / Thiourea Aldehyde to 2- amino-4H-1, 3-Oxazines or Different catalysts like Trifluoro-acetic acid, glacial acetic acid under reflux condition Mandal Co-workers have utilized perchloric (HClO4) supported on silica gel as c...

2950 1 2002 WILEY-VCH Verlag GmbH&Co. KGaA, Weinheim 0044-8249/02/4116-2950 $ 20.00+.50/0 Angew. Chem. Int. Ed. 2002, 41, No. 16 n) V. Krμl, O. Rusin, J. Charvμtovμ, P. Anzenbacher, Jr., J. Fogl, Tetrahedron Lett. 2000, 41, 10147 ± 10151; o) N. Sugimoto, D. Miyoshi, J. Zou, Chem. Commun. 2000, 2295 ± 2296. [6] Studies in polar or apolar organic media: a) R. P. Bonar-Law, A. P. Davis, B. A. Murr...

Irradiation-induced anisotropic swelling in hexagonal α-SiC is known to degrade the mechanical properties of SiC; however, associated physical mechanism and microstructural process remain insufficiently understood. In this study, an condition where surface normal direction was allowed freely expand with constraint lateral introduced 4H-SiC using selected-area He+ irradiation, internal defect di...

Highly uniform step and termination structures on 4Hand 6H-SiC(0001) surfaces have been prepared via moderate annealing in disilane. Atomic force microscopy and dark-field low-energy electron microscopy imaging indicate single-phase terminations separated solely by half-unit-cell-height steps, driven by stacking fault energy. The atomic structure of 4H-SiC(0001)p 3 p3R30 -Si has been determined...

In the present investigation, a series of 4-(4-(dimethylamino) benzyl)-3-methyl-1Hpyrazol-5(4H)-one analogues of pyrazole were synthesized by cyclization of mannich base with hydrazine hydrate. The nitrogen functionality of 4-(4-(dimethylamino) benzyl)-3-methyl-1Hpyrazol-5(4H)-one was alkylated with different halogenated alkylated substituted chain in the presence of base. The chemical structur...

The synthetic access to 2-sec-amino-4H-3,1-benzothiazin-4-ones 2 was explored. Compounds 2 were available from methyl 2-thioureidobenzoates 1, 2-thioureidobenzoic acids 3, and novel 2-thioureidobenzamides 6, respectively, under different conditions. 2-Alkylthio-4H-3,1-benzothiazin-4-ones 5 have been prepared from anthranilic acid following a two step route. Both, benzothiazinones 2 and 5 underw...

In this study, nano-scale honeycomb-shaped structures with anti-reflection properties were successfully formed on SiC. The surface of 4H-SiC wafer after a conventional photolithography process was etched by inductively coupled plasma. We demonstrate that the reflection characteristic of the fabricated photodiodes has significantly reduced by 55% compared with the reference devices. As a result,...

We use three dimensional kinetic Monte Carlo simulations on super-lattices to analyze the nucleation and evolution of several defects during the homoepitaxial growth of 4H silicon carbide. We show also that stacking faults can either extend throughout the entire epilayer (i.e. extended from the substrate up to the surface) or close in dislocation loops, in dependence of the surface kinetics, fi...

A series of pentacyanoferrate complexes, N a3[F e (C N )5L ] /jH20 , where L = (C H 3) 2N H , (C 2H 5) 2N H , (C 2H 5)3N , (C 3H 7)2N H , (C 4H 9)2N H , (C 4H 9)3N and (C 6H 5)2N H were studied by Mössbauer and infrared spectroscopy. A ll the complexes exhibited two line spectra with A E Q = 0.73—1.92 mms“1 and <5 = —0.04—0.49 m m s '1 (w.r.t. SNP) and can be divided into two groups with well d...