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An apparatus based on a Cahn Electrobalance was built in order to study simultaneously, and on the same sample, decomposition reactions by differential thermal analysis and thermogravimetric analysis. The apparatus is comparatively inexpensive and enables reactions to be studied in vacuo, or in any chosen atmosphere. Samples of 20 – 25 mg, both inorganic (for example copper sulfate pentahydrate and calcium oxalate monohydrate) and organic (for example cellulose), give satisfactory results.

The reaction of 1, 1‐diarylethylenes with seleninyl chloride (SeOCl2) and with diselenium dichloride (Se2Cl2) to yield benzoselenopheno [2,3‐b] benzoselenophens was investigated by NMR. Several reaction intermediates have been tentatively identified in the reaction of 1, 1‐diphenylethylene, but its para‐substituted derivatives yielded no additional mechanistic information. The reaction of 1, 1‐diphenylethylene with thionyl chloride was also studied by NMR. Both the SeOCl2and the SOCl2reactions occur through analogous primary addition compounds.

The thermal decomposition of four different cellulose samples (untreated cellulose, powdered or ball‐milled Whatman 544 filter paper, and micro‐crystalline cellulose) was studied at 250°. In samples heated either alone or in the presence of NaHSO4, Na2SO4, Na3PO4, or NaCl for 2 or 4 hr, weight loss, total organic volatiles, levoglucosan, water, acids, average degree of polymerization, and crystallinity index were determined. The results obtained are tabulated and compared. Whereas pretreatment and crystallinity considerably affect the pyrolytic behavior of the different samples, the presence of additives tends to mask the observable differences.

The thermal decomposition of cellulose in vacuo at 250,275 and 300°C was studied. The decomposition products appearing in different fractions were analyzed and the product ratios at different stages of the reaction were determined. A general scheme is proposed for the process.

The thermal decomposition of D‐glucose labelled with 14C either uniformly or at positions 1, 2 or 6 was studied at 250°C, in the presence of NaHCO3, CH3COONa, NaHSO4, NaH2PO4or oxygen. The aqueous and tarry fractions were analysed and the amount and radioactivity of the evolved carbon dioxide and monoxide were determined. The effect of the additives on the pyrolytic processes, especially on the formation of the oxides of carbon is discussed. The presence of basic additives reduces the selectivity of different carbon atoms in the formation of volatiles. Both oxygen and nitrogen promote the formation of CO.

The decomposition of cellulose, in the absence and presence of additives, has been studied in a combined DTA‐TGA (differential thermal analysis — thermogravimetric analysis) system, in which both determinations were carried out simultaneously and on the same sample. The overall process was found to be endothermic in untreated cellulose and in the presence of acidic catalysts, but changed into an exothermal one in the presence of strong bases.

The thermal decomposition of D‐glucose has been studied in vacuo at 175–275°C. The products were analyzed and their origin involving the various carbon atoms was studied, using glucose samples labelled at various positions with 14C. Mechanisms for dehydration and fragmentation processes are discussed.

The formation of levoglucosan and 1,6‐anhydroglucofuranose in the thermal decomposition of glucose derivatives, such as methyl and phenyl glucosides and oligosaccharides was studied. It was found that the cleavage of glucosidic linkages in general involves both transglycosylation and hydrolysis. Some conclusions relating to the thermal stability of the various glucosides were drawn and the mechanisms of the reaction are discussed.

The reaction between azide ions and 2,4‐dinitrochlorobenzene was found to be of first order in each of the reactants. The reaction is slower in more polar media, and is completely inhibited by acid. The place of azide ions in the nucleophilicity order of aromatic substituting agents is assigned.

Acyloins were investigated as hydrogen donors in thermal reactions. With neat materials, satisfactory yields were obtained when weak oxidants such as mercuric cyanide and other mercuric salts were used as hydrogen acceptors. The reactions show a high degree of selectivity: acyloins alone are oxidized by mercuric cyanide while compounds of related structure do not react. The reactions of neat materials, in the molten state, yield results which clearly differ from those previously obtained in various solvents.