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1.
Babasaheb P. Bandgar Neeta S. Joshi Sampada V. Bettigeri 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):67-71
Summary. A mild and efficient transthioacetalization of aldehyde acetals and oxathioacetals was carried out using 2,4,6-trichloro-1,3,5-triazine
as a mild and inexpensive catalyst. Chemoselective transacetalization is impressive as aldehyde O,O- and O,S-acetals are converted into the corresponding S,S-acetals in the presence of ketones or their acetals and oxathiocetals in nearly quantitative yields. 相似文献
2.
[reaction: see text] A novel Cu(I)-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides with acrylates has been developed. Up to 98/2 exo/endo selectivity and up to 98% enantiomeric excess have been achieved. 相似文献
3.
Malati Raghunath 《Tetrahedron letters》2005,46(47):8213-8216
Among the bisphosphine ligands, we have previously developed Cn-TunePhos (n = 1-6) as a family of ligands with tunable bite angles. The increase in spacer -CH2- groups in this family of ligands causes changes in ligand dihedral angle, which in turn causes P-Pd-P bite angle variation. Pd-catalyzed asymmetric alkylations and cycloadditions have been tested with Cn-TunePhos ligands. This study aims at a possible correlation between ligand bite angles with enantioselectivity of the Pd-catalyzed asymmetric products. 相似文献
4.
Satish N. Dighe Ravindra V. Bhattad Raghunath R. Kulkarni Kishor S. Jain 《合成通讯》2013,43(23):3522-3527
The synergy of the combined use of DMSO and an ionic liquid viz. (bbim)+Br? has brought about a rapid and efficient esterification of sodium carboxylates with acyl and alkyl halides under ambient conditions in excellent isolated yields (90–95%) in short reaction times (12–40 min). 相似文献
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Babasaheb J. Waghmode Sagar H. Patil Mandar M. Jahagirdar Virendra S. Patil Rupali P. Waichal Dipalee D. Malkhede Shivaram D. Sathaye Kashinath R. Patil 《Colloid and polymer science》2014,292(5):1079-1089
It is well accepted that the morphology of the nanomaterials has great effect on the properties and hence their applications. Therefore, morphology of materials has become a focus of research in the scientific world. The present study shows that interfacial polymerization and subsequent self-assembly provides a control over the morphology, nanorod/nanosheet, of polyaniline (PANI) films synthesized by liquid–liquid interface reaction technique and solid–liquid interface reaction technique. The synthesized PANI films and its particulate structure are characterized by using various spectroscopic techniques such as UV–visible, ATR-IR, Raman and XPS. The study confirmed the formation, the structure, the size and shape of particles and morphology of PANI by using analytical techniques namely, SAED, SEM and TEM. An important observation is that doping with HCl significantly improves the nanorod formation at the interface. The doped PANI electrode exhibits a higher area with rectangular shape in CV cycle and better cycle stability when compared with the performance of undoped PANI films. We believe that the results of these studies can give valuable leads to manoeuvre formation of PANI films with desired morphology for various applications. Figure
Time and temperature-dependent morphology of PANI layer leading to the formation of one/two-dimensional structures namely, PANI rods/sheets, is achieved by monitoring of self-assembly of nano particulate film formed at liquid–liquid/solid–liquid interfaces 相似文献
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Babasaheb P. Bandgar Lav S. Uppalla Vaibhav S. Sadavarte 《Monatshefte für Chemie / Chemical Monthly》2000,19(6):949-952
Syntheses of α,β-unsaturated nitroalkenes have been carried out under mild condition using morpholine adsorbed on silica
gel as a novel catalyst. 相似文献
9.
Babasaheb P. Bandgar Vibhav S. Sadavarte Sampada V. Bettigeri 《Monatshefte für Chemie / Chemical Monthly》2002,133(3):345-348
Summary. Benzylic alcohols are selectively converted into their corresponding iodides using KI/H2SO4 supported on natural kaolinitic clay and microwaves.
Received August 20, 2001. Accepted (revised) September 18, 2001 相似文献
10.