Efficient cleavage of sterically hindered boronic esters of asymmetric diols to recover both the diol and a more reactive borane derivative has been a challenging problem. A remarkable borosilicate glass-catalyzed cleavage with thionyl chloride and imidazole proved less useful than hoped for. Potassium bifluoride converts boronic esters to diols and alkyltrifluoroborates. These with chlorosilan...

Differentially protected 1,2-diols were synthesized by enantioselective aldehyde α-oxygenation followed by organomagnesium or -lithium addition. Contrary to a previous report, the resultant diols possess an anti configuration. Good selectivity was achieved regardless of the hybridization state of the nucleophile or the presence or absence of branching. This method was applied to short syntheses...

In the present study, a series of aliphatic polyesters based on succinic acid and several diols with 2, 4, 6, 8, 10 methylene groups, namely poly(ethylene succinate) (PESu), poly(butylene (PBSu), poly(hexylene (PHSu), poly(octylene (POSu), poly(decylene (PDeSu), were prepared via two-stage melt polycondensation method. All semicrystalline materials Tm ranging from 64.2 to 117.8 °C, while their ...

a simple, fast, efficient and environmentally friendly method for synthesis of benzimidazole and its 2-alkyl, aryl and heteroaryl substituted derivatives was developed using zeolite hy. two component cyclolcondensation of 1,2-phenylenediamine (o-phenylenediamine) and commercially available carboxylic acids catalyzed by zeolite hy without any solvent, under microwave irradiation led to formation...

A solvothermal method was used to prepare zinc ferrite spinel oxide (ZnFe₂O₄) using ethylene glycol and 1,4 butanediol as solvent diols, and the influence of diols on the physical properties of ZnFe₂O₄ particles was investigated. The produced particles were characterized by X-ray powder diffraction (XRD), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and nitrogen...

A series of new mesogenic azomethine diols were successfully synthesized by condensation reactions between various chloroalkanols and N,N'-bis(4-hydroxy)-benzylidene-o-toluidine (1). The structures of these compounds were confirmed by CHN, FT-IR, (1)H-NMR, and (13)C-NMR spectrophotometer. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC) an...

The choice of the silyl scavenger shows a substantial influence on the diastereoselectivity of the chromium catalyzed pinacol cross coupling. In the case of the intramolecular cyclization, two competing effects are observed. If the silylation reagents contain chelating heteroatoms in the side chain, a remarkable trans-selectivity is observed. Conversely the cis-diols are preferred if bulky subs...

An actinomycete strain with a great potential to produce bioactive compounds isolated from a laterite soil was identified as Streptomyces sp. MSL based on 16S rDNA sequence analysis. Secondary metabolites produced by the strain in optimized nutrient broth were extracted and analyzed by chromatographic and spectroscopic techniques. Among the different fractions, four diols, viz., (1) (2R,3R)-2,3...

The polymerization pathways of epoxidized and hydroxylated triglycerides with phosphoric acid (H3PO4) were investigated using model reactions. Involved epoxides and diols were derived from oleic acid methyl ester, which was easily monitored by oneand two-dimensional nuclear magnetic resonance (NMR) techniques as well as electrospray ionization mass spectroscopy (ESI-MS). Phosphoric acid played ...

The polarity of polyurethane coats was studied on the basis of the goniometric method for determination of wetting angle values, on the basis of calculated surface free energy (SFE) values by the van Oss-Good and Owens-Wendt methods, and on the basis of polarity measurements with the use of the (1)H NMR spectra. Test polyurethanes were synthesised in the reaction of methylene diphenyl 4,4'-diis...