"C NMR spectra have been recorded for eleven piperidin-4-one oximes and for seven of them 'H NMR spectra have been recorded at 270 MHz. The effect of oxhation on the N M R chemical shitts is discussed.The conformations of the oximes are also discussed, based on the observed chemical shifts. Although several oximes appear to adopt a chair conformation, in the same manner as the corresponding ketones, the oximes of 3,5-dimethyl-2,6-diarylpiperidin-4-ones with cis-methyl groups seem to adopt an asymmetric non-chair conformation. Analysis of the chemical shifts of cis-2,6-dimethylcycloltexanone oxime suggests that this compound also exists in a non-chair conformation, and not in a chair conformation with two axial methyl groups as suggested previously.

Six t(3)-aryl-r(2),c(4)-bisethoxycarbonyl-t(5)-hydroxy-c(5)-methylcyclohexanones (6-11) were synthesized by condensing ArCHO (Ar = Ph, p-O(2)NC(6)H(4), p-CH(3)OC(6)H(4), p-ClC(6)H(4), m-O(2)NC(6)H(4) and m-C(6)H(5)O(6)H(4)) with ethyl acetoacetate in the presence of methylamine and their (1)H and (13)C NMR spectra were recorded. (1)H-(1)H COSY and NOESY spectra were recorded for 6 and 7 and also HSQC and HMBC spectra for 6 and 8. Elemental analysis was carried out for all compounds. The mass spectrum was recorded for 8. All analytical data are consistent with the proposed molecular formulae. Analysis of NMR spectral data suggests that these compounds largely adopt chair conformations with the hydroxyl group occupying an axial orientation and all the other substituents occupying equatorial orientations. Long-range coupling (2-3 Hz) between the OH proton and the axial methylene proton at C-6 is observed in 6, 7, 8 and 11.

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isopropyl esters has been synthesized by adopting a conventional method from cyclic -keto esters. 1 H, 13 C NMR, and IR spectra for all the compounds were investigated. HMBC, HSQC, COSY, and NOESY spectra of the representative compounds were studied. The stereochemistry of a six-membered ring of the fused indazoles resembled that of keto esters. From the HMBC correlations the indazole structure was confirmed as 1H-indazole.The universal requirements on heterocyclic compounds for their potential activities against microorganisms and significance in the pharmaceutical field prompted us to synthesize indazoles from cyclic keto esters. Several pathways have been described for the synthesis of indazoles [1][2][3][4][5].Recently we reported the synthesis and structural studies of r-2,c-4-bis(alkoxycarbonyl)-t-3-arylc-5-hydroxy-t-5-methylcyclohexanone by the condensation of acetoacetic esters with different aromatic aldehydes in the presence of methylamine [6][7][8]. The conformation of the two isopropyl groups of compound 1 was also studied with the help of X-ray crystallography of t-2-aryl-c-4-hydroxy-4-methyl-6-oxocyclohexane-r-1,c-3-dicarboxylic acid diisopropyl ester [9]. The present paper describes the use of the above compounds [8] assynthons for the preparation of 4,5,6,7-tetrahydro-1H-indazole. The synthesis of 4,5-trans-2-alkyl-4-hetaryl-5-ethoxycarbonyl(acetyl)-6-hydroxy-6-methyl-4,5,6,7-tetrahydro-2H-indazole has been reported [10]. Nevertheless, the published NMR spectral data apliesmoreto1H-indazolethan to 2H-indazole. N(2)-Substituted tetrahydroindazoles have been reported in [11].Synthesis of 4,5,6,7-1H-indazoles involves two steps. The first step, condensation of isopropyl acetoacetate with aromatic aldehydes in the presence of methylamine in ethanol, yielded cyclic -keto esters 1-7. They were treated with hydrazine hydrate in ethanol under reflux to give compounds 8-14 (Scheme). The mechanism of this second step was different from the expected one. Dehydration was faster than cyclization, and the cyclic intermediates formed in the reaction course were unstable and easily underwent amido-imidol tautomerism, yielding stable 1H-indazoles.

A new alkali metallo-organic single crystal of Lithium Sodium Acid Phthlate (LiNaP) complex has been synthesized from aqueous solution in the equimolar ratio 3:1:2. Transparent and bulk single crystals of dimension 9 × 4 × 2 mm Li3+ Na + crystallizes in triclinic system with a space group of Pī having cell dimensions a = 7.5451(2) Å; b = 9.8422(3) Å; c = 25.2209(7) Å; α = 80.299(2); β = 89.204(2); γ = 82.7770(10). FTIR measurement was carried out for LiNaP to study the vibrational structure of the compound. The various functional groups present in the molecule and the role of H-bonds in stabilizing the crystal structure of the compound have been explained. Optical absorption properties were studied for the grown crystal using UV-Vis-NIR spectrum. Thermal measurements were carried out for LiNaP to determine the thermal strength as well as to ascertain the hydrated nature of the crystal. Third order nonliner optical studies have also studied by Z-scan techniques. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results of all studies have been discussed in detail.