53952-42-4Relevant articles and documents
Preparation and properties of (hydroxymethyl)boronic acid and its pinanediol ester
Matteson, Donald S.
, p. 1425 - 1429 (2011)
Hydrolysis of diisopropyl (bromomethyl)boronate followed by reaction with pinanediol provides an efficient route to pinanediol (hydroxymethyl)boronate (12), a useful intermediate for asymmetric synthesis. The stability of (hydroxymethyl)boronic acid (10) and its ester 12 have been examined by NMR spectroscopy. Heating for 1h in acidic D2O does not degrade 10 and only affects the pinanediol moiety of 12. Base does not degrade 10 or 12 in several days at 2025°C, but converts either to DCH2OD and CH 3OD in a fewh at 9098C, with a large H/D isotope effect. Pinanediol (bromomethyl)boronate with sodium hydroxide in D2O yields a gross mixture of products.
Controlled formation of tetramethylammonium mono- and diylide
Cristau, Henri-Jean,Plenat, Francoise,Bayssade, Sylvie
, p. 29 - 33 (2007/10/03)
The reaction of tetramethylammonium bromide with n -butyllithium can selectively yield either trimethylammonium methylide or lithium dimethylammonium dimethylide, depending on the reaction conditions, as shown by 13C-NMR analysis of the deuterium-labelled species resulting from acidic trapping with DCl. So a simple synthesis of mono- or twice-functionalised methylammonium salts is allowed from a very usual starting material.
Decomposition of 1,3-Dialkyltriazenes in Aqueous Buffers: Kinetic and Mechanistic Studies
Smith, Richard H.,Denlinger, Cheryl L.,Kupper, Robert,Mehl, Andrew F.,Michejda, Christopher J.
, p. 3726 - 3730 (2007/10/02)
1,3-Dialkyltriazenes, prepared by the reaction of alkyl azides with alkyllithiums, are stable as pure liquids or in aprotic solutions.The kinetics of decomposition of 1,3-dimethyltriazene (DMT) were investigated in buffered, aqueous solutions over the pH range of 9-12.The reaction is acid-catalyzed since the rate is inversely proportional to pH.The invariance of the rate with (cyclohexylamino)propanesulfonic acid (CAPS) buffer concentration at pH 9.5 and the finding of an inverse solvent isotope effect of 0.35 suggest that the reaction follows simple specific acid catalysis in that buffer.Decomposition of DMT in phosphate and carbonate buffers, however, indicated dependence of rate on buffer concentration, although the solvent isotope effects were still less than 1.These data suggested that the reaction in those buffers is catalyzed by specific acid, followed by general base.The kinetics of decomposition of 1,3-diethyltriazene (DET) and 1,3-diisopropyltriazene (DIT) were also studied.DET decomposed slightly more rapidly than DMT in phosphate and carbonate buffers but showed a similar dependence of the rate on the buffer concentration.This triazene also exhibited an inverse solvent isotope effect.DIT, on the other hand, showed a rate that was invariant with phosphate buffer concentration and exhibited a biphasic profile of rate vs. carbonate buffer concentration.The rate of decomposition of DIT was also invariant with the pKa of various buffers and showed an inverse solvent isotope effect.Decomposition of DMT in buffered deuterium oxide resulted in incorporation of deuterium into the product methanol, which indicated that an intermediate product of the reaction was the methyldiazonium ion.The dependence of the rate of decomposition on buffer concentration of DMT and DET is explained in terms of nucleophilic attack of buffer anions on N-2 of the protonated triazenes.The proponated DIT, on the other hand, is seen as dissociating directly to the isopropyl carbonium ion in phosphate buffer and in low concentrations of carbonate buffer.
