23834-42-6Relevant articles and documents
Pathways to Functionalized Heterocycles: Propargyl Rearrangement using B(C6F5)3
Wilkins, Lewis C.,Wieneke, Philipp,Newman, Paul D.,Kariuki, Benson M.,Rominger, Frank,Hashmi, A. Stephen K.,Hansmann, Max M.,Melen, Rebecca L.
, p. 5298 - 5309 (2015)
The reactions of propargyl amides, ureas, carbamates, and carbonates with B(C6F5)3 proceed via an intramolecular 5-exo-dig cyclization across the alkyne unit to yield the corresponding vinyl borate species. The generated sp2 carbocation is stabilized by the flanking heteroatoms, allowing for isolation of oxazoline intermediates. The fate of these intermediates is strongly dependent upon the propargyl-functionalized starting material, with the carbamates and carbonates undergoing a ring-opening mechanism (propargyl rearrangement) to give cyclic allylboron compounds, while prolonged heating of the urea derivatives shows evidence of oxazole formation. In a deviation away from the reactivity of carbamates stated previously, the benzyl carbamate substrate undergoes dealkylation at the benzylic position, liberating 5-methyloxazol-2-(3H)-one.
Method for preparing organophosphate compound from P(O)-OH-containing compound and alcohol through efficient esterification
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Paragraph 0033, (2017/07/21)
The invention provides a method for efficiently and highly selectively synthesizing an organophosphate derivative containing different substitute functional groups. The method is characterized by adopting a polypeptide catalyst as a condensation reagent, taking a P(O)-OH-containing compound and alcohol as reaction substrates, and adding an organic solvent in a reaction system. The method disclosed by the invention has the advantages that the catalyst is cheap in cost and easy to obtain; the substrate applicability is high; reaction conditions are mild, safe and reliable; the selectivity of an obtained target product is close to 100 percent, and the yield is up to 90 percent or more. According to the method provided by the invention, the defects of a traditional method for synthesizing an organophosphate compound that the reaction selectivity is poor, the reaction steps are tedious, the yield is low, reagents which are harmful to the environment are required to be used, and the like are solved, and a good industrial application prospect is obtained. Meanwhile, the invention also provides the corresponding organophosphate derivative containing different substitute functional groups.
