ABSTRACT
I. V. VAKULIN, R. F. TALIPOV, O. YU. KUPOVA, G. R. TALIPOVA, A. V. ALLAGULOVA, and R. R. FAIZULLINA
Abstract ..................................................................................................118 11.1 Introduction .................................................................................118 11.2 Methods of Calculations .............................................................119 11.3 Calculation Results and Discussion ........................................... 120 11.4 Conclusion ................................................................................. 126 Keywords .............................................................................................. 127 References ............................................................................................. 127
ABSTRACT
The role of formaldehyde dimer in O-containing heterocycles formation by the Prins reaction have been investigated. It was shown that the 1,3-dioxanes, hydrogenated pyrans and oxetanes can be can be obtained from formaldehyde dimers and alkenes in the gas phase. The activation energy of these reactions is different. It is lower for 1,3-dioxanes formation, and higher for oxetanes formation. Thus formation of 1,3-dioxanes happens in the conditions of kinetic control. Opposite, the hydrogenated pyrans formation happens in the conditions of thermodynamic control
11.1 INTRODUCTION
The Prins reaction [1] is a convenient technique of oxygen-containing heterocycles formation. It is applied in large-tonnage organic synthesis and total synthesis of complex natural products as well [2]. However, the formation of 4,4-dimethyl-1,3-dioxane along with fair quantities of byproducts reduces practical value of this reaction. Thereupon, the clarification of the Prins reaction mechanism aimed at increasing selective ways of 1,3-dioxanes formation seems to be quite an urgent task.
