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91.
92.
A novel synthetic approach is described to incorporate one more carbon atom at C-2 position of phospholane oxides as homologated allylic alcohol by treatment of erythro-2,3-epoxy-3-methylphospholane 1-oxides with excess of dimethylsulfonium methylide. 相似文献
93.
A mild and highly efficient deoxygenation of variety of N-oxides using an inexpensive CuX, or a CuX-Zn or CuX-Al couple is described. 相似文献
94.
Koteswara Rao Y Vijaya Bhaskar Reddy M Venkata Rao C Gunasekar D Blond A Caux C Bodo B 《Chemical & pharmaceutical bulletin》2002,50(9):1271-1272
Two new 5-deoxyflavones, 7,8-dimethoxy-3',4'-methylenedioxyflavone (1) and 7,2',4'-trimethoxyflavone (2) together with a known flavone, 7,4'-dimethoxy-3'-hydroxyflavone (3) were isolated from the rootbark of Albizia odoratissima. The structures of these new compounds were elucidated by electrospray ionization mass spectrometry (ESI-MS) and 1D and 2D-NMR spectral studies including (1)H-(1)H correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser enhancement spectroscopy (NOESY). 相似文献
95.
V. Naveen Kumar P. Someshwar P. Narsimha Reddy Y. Thirupathi Reddy B. Rajitha 《Journal of heterocyclic chemistry》2005,42(5):1017-1019
The condensation reaction of aldehydes, β‐ketoesters and urea/thiourea in presence of a catalytic amount of CuPy2Cl2 complex proceeded under very mild reaction conditions in high yield (80‐90%). 相似文献
96.
1,4-Disubstituted 1,2,3-triazoles are obtained in excellent yields via a three-component coupling of secondary alcohols, alkynes and trimethylsilyl azide (TMSN3). This one-pot reaction occurs through in situ generation of an azide from the alcohol and TMSN3, followed by 1,3-dipolar cycloaddition of the terminal alkyne to afford the corresponding disubstituted triazoles. 相似文献
97.
Polyethylene glycol (PEG) is found to be an inexpensive, nontoxic, environmentally friendly reaction medium for the conjugate addition of thiols to conjugated alkenes to afford the corresponding adducts in excellent yields under mild and neutral conditions. Products of undesirable side reactions resulting from polymerization are not observed. The use of PEG avoids the use of either acid or base catalysts for this conversion and moreover PEG can be recovered and reused. 相似文献
98.
Benzathine is prepared in good yields from cyanobenzene by a combination of electrochemical hydrogenation and Kolbe electrolysis using nickel and platinum electrodes in the presence of methanolic sodium methoxide in an undivided cell. 相似文献
99.
Some new metal-containing polyurethanes were synthesized from manganese and lead salts of mono(hydroxyethyl)phthalate by condensing them with hexamethylene diisocyanate and toluene diisocyanate in dimethylformamide as solvent. The polymers were characterized by viscometry, infrared spectroscopy and thermal analysis. The decomposition temperatures of these polymers were found to be significantly lower than those of metal-free polymers of similar structure. However, the rates of decomposition of metal-containing polyurethanes were lower than those of polyurethanes having no metal. Inherent viscosities in DMSO at 30° of these polyurethanes were low, ranging from 0.043 to 0.067. 相似文献
100.
Venkatapuram Padmavathi Pinnu Thriveni Boggu Jagan Mohan Reddy Adivireddy Padmaja 《Journal of heterocyclic chemistry》2005,42(1):113-116
A new class of five membered heterocycles, thiadiazoles, triazoles and oxadiazoles were prepared from sulfonyl acetic acids via acid hydrazides. 相似文献