The following reactions to convert acetone cyanohydrin (1) into methyl methac- rylate (2) were studied. The hydrolysis of (1) was effected by using 1.5 mol sulfuric acid per mole of (1) at 80°C for 1-2 hrs with subsequent raise in temperature to 130°C for 0.5 hr with stirring. For the esterif ication, a methanol/water molar ratio of 2/3 wasemployed at 80°C for 3 hrs. Thus, (2) was obtained in an over-all yield of 851. The apparent activation energy for the hydrolysis of methacrylonitrile (3) was about 10.3 Kcal/mol and the reaction was found to be second order in the concentrations of (3) and water. The esterification of methacrylic acid (4) in the presence of sulfuric acid was also tested. The apparent activation energy was found to be 24.4 Kcal/mol and the reaction was first order in the concentration of (4).
It had been known that the Kolbe-Schmidt reaction for the synthesis of hydroxybenzoic acids from alkali phenoxide and carbon dioxide was inhibited in the presence of water. In the present study, however, the desired reaction was found to occur in an aqueous medium in the presence of alkali carbonates . Thus the effects of the amounts of alkali carbonates, reaction temperatures, reaction times, and the initial pressures of carbon dioxide on the yields of salicylic acid, p-hydroxy benzoic acid, and 4-hydroxyisophthalic acid were investigated. It has also been found that, in an aqueous solution, the hydroxybenzoic acids were thermally unstable. They decompose into phenol, which, in turn, is re-carboxylated to form hydroxybenzoic acids in the presence of alkali carbonates to reach an equilibrium state.
Furfural, 5-bromo-2-furfural, and 5-nitro-2-furfural were treated in tetrahydrofuran with ethynylmagnesium bromide to give the corresponding furylethynylcarbinols in yields of 35, 22, and 6%, respectively. Furfural afforded furylpropargylcarbinol in only 2% yield, when treated with propargyl magnesium bromide in ether . Oxidative coupling reaction and the Mannich reaction were carried out using furylethynylcarbinol. Mercury derivatives of furyl- and 5-bromo-2-furyl ethynylcarbinols were prepared by the McEwen's method. The sodium acetylide of furylethynylcarbinol was condensed with ethyl chlorocarbonate . The preparative method of 5-nitro-2-furylpropiolic acid was reinvestigated and the yield was improved up to 60%. 5-Nitro-2-furylacetylene was synthesized by the following three methods: 1) decarboxylation of 5-nitro-2-furylpropiolic acid, 2) dehydrobromination of 5-nitro-2-furylbrornoethylene, and 3) dehydrobromination of β-(5-nitro-2-furyl)-α-bromopropenal. Though the oxidative coupling reaction and mercuration of 5-nitro-2-furylacetylene proceeded smoothly, the Mannich reaction did not take place.
When a N-(substituted benzenesulfonyl)-N'-alkyl carbodiimide (1) was treated with an equimolar amount of pyridine (2) in the absence of solvent, an addition compound (3) of (1) and (2) was formed. In the presence of solvent, however, a dimer (4) of (1) was obtained. Furthermore, (3) was converted quantitatively into (4) when dissolved in an organic solvent, such as chloroform. Thus, it is assumed that the carbodiimide is dimerized through an intermediary addition compound (3). (4) was then hydrolyzed into a N-(substituted benzenesulfonyl)-N', N"-dialkylguanidine, a N-substituued benzenesulf onamide, and carbon dioxide in a theoretical yield. Based on the hydrolysis products, the structures of (4) and (3) were elucidated.
Though a pyrazole hydroazine vat dye (1) was formed by the direct cyclization of pyrazoleanthrone with 1-amino-2-bromoanthraquinone, the yield was as low as 10%. I, however, was obtained in 58% over-all yield in a two -step synthesis via cyclization of the intermediate, 2-(1'-amino-2-anthraquinonyl)-pyrazoleanthrone, in pyridine-methanol containing potassium hydroxide . 2-(2'-Aminophenyl)-pyrazoleanthrone was also readily cyclized into a pyrazole hydroazine compound . Similar reactions using 2-(3'-pyrazoleanthronyl)-pyrazoleanthrone and 3-anilino - pyrazoleanthrone, however, failed to take place. It is assumed that the cyclization reaction proceeds through a link formation between a -NH anion formed as shown below and a carbonium cation induced by the electron withdrawing effect of the carbonyl group in the pyrazoleanthrone ring.