An efficient method is described for the mild and rapid tetrahydropyranylation of alcohols and phenols using a catalytic amount of N-chlorosaccharin (1 mol %) and 3, 4-dihydro-2H-pyran under solvent-free condition at room temperature. Benzylic alcohols and phenols containing electron withdrawing or donating groups in various positions of phenyl ring, cinamyl alcohol, primary, ...

The aromatization of 2-octanol derived from castor oil as a byproduct in the formation of sebacic acid was investigated on various zeolite catalysts. Zn ion-exchanged MFI (ZSM-5) zeolites with small silica/alumina ratios and zinc contents of 0.5 to 2.0 wt. % were determined to exhibit good and stable activity for the reaction at 623 to 823 K. The yield of aromatics was 62% at 773 K and the spac...

Acid catalysis by hydronium ions is ubiquitous in aqueous-phase organic reactions. Here we show that hydronium ion catalysis, exemplified by intramolecular dehydration of cyclohexanol, is markedly influenced by steric constraints, yielding turnover rates that increase by up to two orders of magnitude in tight confines relative to an aqueous solution of a Brønsted acid. The higher activities in ...

The systematic oxidation reactions of a wide range of alcohols have been carried out by using an iron porphyrin complex in order to understand their relation to cytochrome P-450 enzymes and to have a practical application to organic synthesis. The iron porphyrin complex catalyzed efficiently alcohol oxidation to the respective carbonyl compound via a high-valent iron-oxo porphyrin intermediate ...

Tissue from 73 chick embryos incubated for periods between 1 and 13 days has been studied. Before fixation each specimen was staged according to the normal table of Hamburger & Hamilton (1951). The tissue was fixed either in osmium tetroxide, or in potassium permanganate (Luft, 1956). In either case the pH was buffered to 7-4 with sodium veronal (Palade, 1952) and fixation was at 0° C. In the e...

Tissue from 73 chick embryos incubated for periods between 1 and 13 days has been studied. Before fixation each specimen was staged according to the normal table of Hamburger & Hamilton (1951). The tissue was fixed either in osmium tetroxide, or in potassium permanganate (Luft, 1956). In either case the pH was buffered to 7-4 with sodium veronal (Palade, 1952) and fixation was at 0° C. In the e...

White discoloration on peeled carrots is partially due to surface dehydration which can be controlled with hygroscopic coatings: e.g., polyhydric alcohols and salt solutions. This study was performed at 2.5, 7.5, 10, and 157C, using a model system controlling relative humidity at 33, 75 or 98% or a commercial system with low-density polyethylene (LDPE) plastic film bags. The moisture sorption p...

Pervaporation (PV) is a well-established membrane technique used in separation; especially dehydration of organic solvents. Along with other parameters such as permeate pressure and feed temperature; feed composition is an important parameter, which affects separation characteristics and membrane performance in pervaporation. In this paper, the separation characteristics of a hydrophilic polyvi...

A new synthesis of a-hydroxycarboxylates and 2-hydroxybenzoates based on the reaction of acetonides of a-hydroxycarboxylic acids and 2-hydroxybenzoic acid with sodium alkoxides in the corresponding alcohols as solvent is described. In general, decreasing the steric hindrance of the reactants and increasing the boiling points of alcohols increased the yiel...

although several methods for the preparation of 4o propargyl indole derivatives have been published, this synthetic transformation is complicated by the tendency of 3o propargyl alcohols to form allenium intermediates in acidic media.  it is therefore a challenge to find an efficient method for the c-3 propargylation of indoles with 3° propargylic alcohols.  in this paper we wish to report on t...