An efficient strategy for the multicomponent synthesis of pyrimidine analogues has been demonstrated via acceptorless dehydrogenative annulation (ADA) of alcohols utilizing new Ni(II)-NNO pincer complexes as catalysts. The newly formed Ni(II) complexes (-) featuring N^N^O chelating hydrazone ligands are well established through analytical and spectral methods (FT-IR and NMR). Single-crystal X-ray diffraction analysis precisely reveals the NNO coordination fashion and square planar geometry around the metal center.
View Article and Find Full Text PDFThe structure of the 4-(4-chlorobenzyl)-2-(1-methylazepan-4-yl) phthalazin-1(2H)-one (IA) was optimized through computational study. The optimized structure revealed that the bond length between atoms C3 and C5 was the longest at 1.54 Å, while the bond between atoms C10 and H31 had the lowest length at about 1.
View Article and Find Full Text PDFA facile, cost-effective, and sustainable synthesis of substituted triazines from primary alcohols by newly synthesized nickel pincer-type complexes (-) has been described. Herein, we report the synthesis of a set of three well-defined Ni(II) O^N^O pincer-type complexes, structurally characterized by analytical, spectral, and X-ray diffraction techniques. Further, the nickel complexes are explored as efficient catalysts (4 mol %) for the construction of 2,4,6-substituted 1,3,5-triazines from readily available alcohols via an acceptorless dehydrogenative coupling (ADC) strategy.
View Article and Find Full Text PDFWe report the atom-economic and sustainable synthesis of biologically important 3,4-dihydro-2-1,2,4-benzothiadiazine-1,1-dioxide (DHBD) derivatives from readily available aromatic primary alcohols and 2-aminobenzenesulfonamide catalyzed by nickel(II)-N∧N∧S pincer-type complexes. The synthesized nickel complexes have been well-studied by elemental and spectroscopic (FT-IR, NMR, and HRMS) analyses. The solid-state molecular structure of complex 2 has been authenticated by a single-crystal X-ray diffraction study.
View Article and Find Full Text PDFWe demonstrate an efficient and sustainable strategy for the direct synthesis of 2,4-disubstituted quinazolines by arene Ru(II)benzhydrazone complex the eco-friendly sequential acceptorless dehydrogenative coupling of 2-aminobenzhydrol derivatives and benzyl alcohols for the first time. The new ruthenium(II) complex of the general formula [(η--cymene)Ru(L1)Cl] (L1-acenaphthenequinone hydrazone) has been synthesized and characterized by analytical, spectroscopic, and single-crystal X-ray diffraction techniques. A broad spectrum of 2,4-disubstituted quinazolines have been successfully derived (25 examples) from 2-aminobenzhydrol derivatives with various benzyl alcohols using 1 mol % of catalyst loading in the presence of NHOAc.
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