Synthesis, Characterization and Investigation of Second- Harmonic Generation Efficiency of Azetidinone Derivatives Encompassing 3-Nitronaphtho[2,1-B]FuranAuthor(s): K. Shashikala Devi, M. Ramaiah, K. Veena and V. P. Vaidya
In the last few decades, nonlinear optical materials are getting attention in the field of optical data storage, telecommunication, second harmonic generation (SHG) and optical signal processing, etc. In the present work, we are reporting the synthesis and non-linear optical (NLO) property of new naphthofuran derivatives. Second harmonic generation (SHG) efficiency has been observed in the target molecules. Ethyl 3-nitronaphtho[2,1-b]furan-2-carboxylate 2 has been synthesized from ethyl naphtho[2,1-b]furan-2- carboxylate 1. This nitro product on reaction with hydrazine hydrate formed 3-nitronaphtho[2,1-b]furan-2- carbohydrazide 3. Various Schiff’s bases i.e. 3-nitro-N1 (aryl-methylene)-substituted-naphtho[2,1-b]furan- 2-carbohydrazides 4(a-g) were obtained by treating hydrazide 3 with different aromatic aldehydes. These Schiff bases on reaction with chloro acetyl chloride in presence of triethylamine as catalyst in dioxane yielded 3-nitro-N-(3-chloro-2-oxo-substituted-phenyl-azetidine-1-yl)naphtho[2,1-b]furan-2-carboxamides 5(a-g). The newly synthesized compounds were characterized by analytical and spectral studies. The second harmonic generation (SHG) efficiency of these compounds was measured by powder technique using PROLAB 170 laser. Among tested compounds three naphthofuran derivatives showed NLO property. Compounds, 5a exhibited NLO property with SHG conversion efficiency 0.12 times that of potassium dihydrogen orthophosphate (KDP), compound 5c exhibited NLO property with SHG conversion efficiency 0.42 times that of KDP, compound 5e exhibited NLO property with SHG conversion efficiency 0.21 times that of KDP.