34619-03-9Relevant articles and documents
-
Parham,Loew
, p. 1705,1707 (1958)
-
Production of carbonate
-
Paragraph 0064; 0119-0121, (2016/12/22)
PROBLEM TO BE SOLVED: To provide a method for producing a carbonic acid ester, which enables a high reaction speed and a high reaction rate by reacting a monohydric alcohol with carbon dioxide in the presence of a solid catalyst, even under a mild reaction condition of relatively low pressure. SOLUTION: A monohydric alcohol is reacted with carbon dioxide in the presence of a solid catalyst and a nitrile compound to form a carbonic acid ester and water, an amide compound is formed by a hydration reaction between the nitrile compound and the formed water, and the formed water is removed from the reaction system or reduced to promote the formation of the carbonic acid ester. COPYRIGHT: (C)2012,JPOandINPIT
The Mechanism of Thermal Eliminations. Part 15. Abnormal Rate Spread in Pyrolysis of Alkyl Methyl Carbonates and S-Alkyl O-Methyl Carbonates due to Enhanced Nucleophilicity of the Carbonyl Group
Taylor, Roger
, p. 291 - 296 (2007/10/02)
Rate coefficients for pyrolytic elimination of ethyl, isopropyl, and t-butyl carbonates, and of di-t-butyl carbonate have been measured over a 50 K range for each compound.The relative rates at 600 K are 1:29.6:2934:3526 and the rate spread for the primary, secondary, and tertiary compounds is inconsistent with that obtained from elimination of a range of other esters including alkyl phenyl carbonates.The least reactive compounds are found to be more reactive than predicted, probably owing to a combination of the greater Ei character of their transition states and the high nucleophilicity of the carbonyl group in dialkyl carbonates.Rate data for pyrolysis of S-ethyl, S-isopropyl, and S-t-butyl O-methyl carbonates give the relative rates at 600 K as 1:22:1074.The But:Pri rate ratio (49:1) is therefore greater than the Pri:Et ratio, as it is for all other related eliminations; this confirms that the literature results (which show the converse) are in error.The seemingly anomalous relative reactivities of thiolacetates and thiolcarbonates as compared with their oxygen-containing analogues is also shown to be consistent with the effect of variable polarity of the transition state in ester pyrolysis upon the importance of carbonyl group nucleophilicity, and this also accounts for the relative reactivities of thiol-, thion-, and dithio-acetates.Steric acceleration appears less important for carbonates than for acetates, since the rate for di-t-butyl carbonate (statistically corrected) is lower than for t-butyl methyl carbonate, whereas pivalates are more reactive than acetates.
