3 results about "Fluoroacetates" patented technology

The invention discloses a preparation method of an alkynyl bicyclo [3.1. 1] heptane difluoroacetate compound in the technical field of organic synthesis, which comprises the following steps: by taking terminal alkyne, [3.1. 1] propeller alkane and gem-difluorobromoacetate as initial raw materials, under the condition that the stoichiometric copper acetylacetonate and 1, 8-diazabicyclo [5.4. 0] undec-7-ene (DBU) are taken as alkalis and acetonitrile is taken as a solvent, carrying out a reaction on the initial raw materials to prepare the alkynyl bicyclo [3.1. 1] heptane difluoroacetate compound. The reaction is carried out through a one-pot method. The process comprises the following key steps: firstly, generating high-activity gem-difluoroacetate free radicals from gem-difluorobromoacetate; the free radical and high-tension [3.1. 1] propeller alkane are subjected to ring-opening addition, ring tension is released, and a new carbon center free radical intermediate is generated; the intermediate is then captured by alkynyl copper species generated in situ, and finally a target product is obtained through reduction elimination. The method is mild in reaction condition and wide in substrate universality, the problems of tedious synthesis steps and low efficiency in the prior art are solved, and a novel and efficient way is provided for preparation of the important molecules.

This invention relates to the field of organic synthesis, specifically to a method for the preparation of difluoroenones and their in-situ reaction with amines, alcohols, etc., to convert them into the corresponding difluoroacetamides and difluoroacetic acid esters. The invention involves sequentially adding potassium fluoride, an amine or alcohol, and a difluorobromoacrylsilyl compound to a reaction solvent under a nitrogen atmosphere to obtain a mixture. This mixture is stirred at 25°C until the reaction is complete, filtered, and purified to obtain the difluoroacetamide or difluoroacetic acid ester compound. The preparation method of this invention is simple to operate (highly reactive difluoroenones are generated in situ and participate in the reaction), achieving efficient synthesis of difluoroacetamide / difluoroacetic acid esters and avoiding the use of highly volatile difluoroacetyl chloride. The difluorobromoacrylsilyl used in this invention can be conveniently prepared on a large scale and can be purified by distillation. The reaction conditions involved in the preparation method of this invention have good substrate tolerance and can be applied to aliphatic amines, aromatic amines, and various primary and secondary alcohols.