Abstract Phosphinic acids may be efficiently esterified in microwave-assisted reactions with alcohols. Especially alcohols with longer alkyl chain are suitable reagents for direct esterifications. At the same time, the directamidation cannot be complete under such conditions. Hence, the tradional amidations via the phosphinic chloride intermediates have to be applied. The values of activation enthalpies
It is well-known that phosphinicacids do not undergo directesterifications with alcohols under thermal conditions. However, the esterifications take place under microwave (MW) irradiation due to the beneficial effect of MW. As a comparison, maximum 12-15% conversions were observed on traditional heating. It was proved experimentally that the MW-assisted esterifications are not reversible under the
The Synthesis of 3-Phosphabicyclo[3.1.0]- hexane 3-Oxides and 1,2-Dihydrophosphinine 1-Oxides with Lipophilic P-Alkoxy Substituents by Ring Enlargement
1-alkoxy-3-phospholene 1-oxides available from the microwave-assisted direct esterification of 1-hydroxy-3-phospholene oxide was converted to the two diastereomers of 6,6-dichloro-3-phosphabicyclo[3.1.0]hexane 3-oxides by the addition of dichlorocarbene to the double bond. Thermolysis of the 3-phospholene oxide–dichlorocarbene adducts afforded the corresponding 1,2-dihydrophosphinine 1-oxides as a ca. 3:1 mixture