The Synthesis Of Difluoromethlene-Containing Benzoyl Compounds

Fluorinated compounds are widely used in the pharmaceutical chemistry, materials and life sciences and other fields due to their unique physicochemical properties and bioactivity.Especially, the compounds containing CF2 show excellent bioactivity. Among those compounds, difluoromethlene-containing benzoyl compounds have attracted much attention due to their synthetic applications and potential bioactivity. In past few years, although the methods of introducing the CF2 group into organic molecules have been largely reported,efficient strategies for the construction of difluoromethlene-containing benzoyl compounds are in fancy. In this dissertation, we synthesized kinds of functionalized fluorine-containing building blocks: a,a,a-iododifluoroacetones , which were served as fluorided agent and used in the radical reaction with alkynes, and then three component reaction withα,α,α-iododifluoroacetones , alkynes and phenylboronic acid as substrates was investigated,providing a new path the synthesis for difluoromethlene-containing benzoyl compoundsIn the second chapter, we synthesized a series of a,a,a-iododifluoroacetones and explored the reactions with various alkynes. The optimum conditions were screened, i.e. 20 mol% AIBN as radical initiator, neatly, and under N2 atmosphere, 80 ℃, 12 h affording various functionalized difluoromethlene-containing vinylic iodides, with up to 88% yield and high stereoselectivity, which can obtain functionalized multisubstituted difluoromethlene-containing compounds by further functionalization. Finally,a preliminary reaction mechanism was discussed. This chapter contains 9 fluorine-containing building blocks, 19 adducts and 2 coupling products.In the third chapter, The three component reaction involving α,α,α-iododifluoroacetones,alkynes and phenylboronic acid as substrates was investigated. We screened catalyst, base,sovent and temperature et al., and the optimum conditions were obtained. i.e. 5 mol%Pd(PPh3)4 as catalyst, K3PO4 (2 equiv)as base, toluene as solvent, and under N2 atmosphere,60 ℃, 12h affording target products with good yield. This chapter contains 10 functionalized difluoromethylenated benzoyl compounds.