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51.
52.
Balinge Kamlesh Rudreshwar Khiratkar Avinash Ganesh Muskawar Prashant Narayan Thenmozhi K. Bhagat Pundlik Rambhau 《Research on Chemical Intermediates》2018,44(3):2075-2097
Research on Chemical Intermediates - The synthesis of polymer supported zinc–salen complex (PS-Zn–salen) is described. The mononuclear zinc(II)–salen complex was characterized by... 相似文献
53.
Avinash K. Srivastava Munsaf Ali Kamal Nayan Sharma Raj K. Joshi 《Tetrahedron letters》2018,59(33):3188-3193
A toluene solution of β-chlorocinnamaldehyde and dihydroxy alcohols in the catalytic presence of para-toluenesulphonic acid (PTSA) yield the β-ketoacetal in good to outstanding amount. The catalyst (PTSA), first selectively protect the aldehydic group to form the β-chloroacetal and the subsequent dechlorination by H2O result the β-ketoacetal. Significant transformation was achieved with electron donating substituent attached at the para-position of cinnamaldehyde. The selective formation of β-keto-1,3-acetal was also obtained with a mixture of 1, 2- and 1, 3- diol. The present reaction consists of a metal-free, economical, robustly feasible, sizeable functional group tolerance and high yield properties. Moreover, the use of different dihydroxy alcohols made this process more benign and valuable towards the metal-free development of ketones. First, of its kind, a rare and unusual multitasking nature of PTSA is observed. 相似文献
54.
Murali Krishna Kolli Palani Elamathi Vishweshwar Rao Katta Gajendrasinh Balvantsinh Raolji 《合成通讯》2018,48(6):638-649
One-pot synthesis of α-aminophosphonates directly from aryl nitro compounds, aldehydes/ketones, and diethyl phosphite using sodium dithionite through reduction and followed by Kabachnik–Fields reaction under metal-free conditions is reported. The major advantages are excellent yield, high chemoselectivity, neutral reaction medium, and simple experimental procedure. This methodology consists of the following steps: 1) amine formation from nitro compound, 2) imine formation from amine and aldehyde/ketone, 3) phosphate addition to imine. 相似文献
55.
Avinash Kumbhar Pramila Sonawane Subhash Padhye Douglas X. West Ray J. Butcher 《Journal of chemical crystallography》1991,27(9):533-539
The structures of two antitumor agents, 2-acetylpyridinethiosemicarbazone hemihydrate (1), C18H11N4O0.5S, colorless,M
r
203.3, monoclinic,P21
lc,a=16.713(3),b=9.460(2),c=12.642(2) ?, β=97.60(1)°,V=1981.2(6) ?3,Z=8,R=0.054,R
w
=0.085 and 2-acetylpyridinethiosemicarbazone hydrochloride (2), C18H12N4SCl, yellow,M
r
=230.7, monoclinic,P21
ln,a=7.676(2),b=7.889(1),c=17.452(4), ?, β=100.96(2)°,V=1037.5(4) ?3
Z=4,R=0.041,R
w
=0.076, have been determined. Both compounds exhibit an E configuration(S atomtrans to the N atom of the hydrazine group). Three hydrogen bonds link the two crystallographically independent molecules in a
pairwise fashion in the hemihydrate. An intramolecular N−H...Cl bond lends extra conformational stability to the hydrochloride
salt. 相似文献
56.
The isolation and characterization of an unusual spiroanthracene, from the reaction of bisdichlororuthenium(II)bipyridine dihydrate with 3-(9-anthrylmethyl)pentane-2,4-dione (AMPD), is reported. This metal-promoted formation of spiroanthracene has been obtained for the first time during the synthesis of metal complexes. 相似文献
57.
Avinash S. Kumbhar Mahesh P. Mulay Subhash B. Padhye Sudam S. Tavale Vedavati G. Puranik 《Structural chemistry》2008,19(5):735-740
Crystal structure of {[Mn(salicylaldoximeH)(salicylaldoxime)]4} · 3CHCl3 1 formed by the interaction of MnCl2 · 4H2O and salicylaldoxime in a 1:1 ratio is described. The compound crystallizes in the orthorhombic space group Pbca (No 61) with the lattice parameters; a = 27.769 (3), b = 22.672 (2), c = 21.650 (2) Å, V = 13630 (2) Å3, Z = 8, R 1 = 0.0776, wR 2 = 0.2356, S = 1.164. The cluster with four Mn (III) centers formed by four terminal and four bridging salicylaldoxime ligands results in a central rotating wheel-like core with the Mn–Mn separation varying from 3.531 to 3.576 Å and with the diagonal distances being 4.156–4.165 Å. Four intramolecular H-bonds between a terminal oxime (NOH) group and the adjacent phenolate oxygen atom of another ligand stabilize the structure of the cluster. Spectral, magnetic, and cyclic voltammetry studies corroborate a stable Mn (III) tetramer. 相似文献
58.
59.
Sakharam B. Tayade Datta Markad Avinash S. Kumbhar Andrea Erxleben Debamitra Chakravarty 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(8):1084-1090
Two new one‐dimensional (1D) coordination polymers (CPs), namely catena‐poly[[[aquacadmium(II)]‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Cd(C14H10N6O2)2(H2O)](ClO4)2·2H2O}n or {[Cd(BPG)2(H2O)](ClO4)2·2H2O}n, 1 , and catena‐poly[[lead(II)‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Pb(C14H10N6O2)2](ClO4)2·2H2O}n or {[Pb(BPG)2](ClO4)2·2H2O}n, 2 , have been synthesized using bipyridine–glycoluril (BPG; systematic name: 4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione), a urea‐fused tecton, in a mixed‐solvent system. The CdII ion in 1 is heptacoordinated and the PbII ion in 2 is hexacoordinated, with the CdII ion adopting a pentagonal bipyramidal geometry and the PbII ion adopting a distorted octahedral geometry. Both CPs form infinite linear chain structures which are hydrogen bonded to each other leading to the formation of three‐dimensional supramolecular network structures. Topological analysis of CPs 1 and 2 reveals that the structures exhibit 1D chain‐like arrangements in an AB–AB sequence and shows platonic uniform 2‐connected uninodal topologies. Furthermore, a comparative analysis of a series of structures based on the BPG ligand indicates that the size of the metal ion and the types of counter‐ions used have a great influence on the resulting frameworks and properties. 相似文献
60.
Lianbing Zhang Avinash J. Patil Dr. Le Li Angelika Schierhorn Dr. Stephen Mann Prof. Ulrich Gösele Prof. Mato Knez Dr. 《Angewandte Chemie (International ed. in English)》2009,48(27):4982-4985
New uses for ALD : By applying standard metal oxide atomic layer deposition (ALD) to two types of porphyrins, site‐specific chemical infiltration of substrate molecules is achieved: Diethylzinc can diffuse into the interior of porphyrin supramolecular structures and induce metalation of the porphyrin molecules from the vapor phase. A=Ph, p‐HO3SC6H4.