Abstract: Disclosed is a preparation method for cannflavin compounds. The preparation method has the advantages of cheap and easily available raw materials, few reaction steps, short production period, simple operation, etc. The method comprises: firstly, condensing 4?-hydroxy-3?-methoxyacetophenone and diethyl carbonate (DEC) under an alkaline condition to obtain 4?-hydroxy-3?-methoxybenzoyl acetate; reacting 1,3,5-trihydroxybenzene with bromo-isoamylene under an alkaline condition to obtain 2-isopentenyl-1,3,5-trihydroxybenzene; and finally, condensing 4?-hydroxy-3?-methoxybenzoyl acetate and 2-isopentenyl-1,3,5-trihydroxybenzene at a high temperature to produce cannflavin B and/or isocannflavin B, and then subjecting same to separation and purification to obtain pure cannflavin B and pure isocannflavin B.

Abstract: Disclosed in the present invention is a preparation method for cannflavin compounds. The preparation method has advantages such as cheap and easily available raw materials, few reaction steps, short production period, and easy operation. The method comprises: first, condensing 4?-hydroxy-3?-methoxyacetophenone and diethyl carbonate (DEC) under an alkaline condition to obtain ethyl 4?-hydroxy-3?-methoxybenzoylacetate, next, reacting 1,3,5-trihydroxybenzene with geraniol to obtain (E)-2-(3,7-dimethyloct-2,6-dien-1-yl)benzene-1,3,5-triphenol; and finally, condensing ethyl 4?-hydroxy-3?-methoxybenzoylacetate and (E)-2-(3,7-dimethyloct-2,6-dien-1-yl)benzene-1,3,5-triphenol at high temperature to produce cannflavin A and/or cannflavin C, and then carrying out separation and purification to obtain pure cannflavin A and cannflavin C.

Abstract: The present invention relates to a method for synthesis of o-diphenylphosphinobenzoic acid which includes the steps as follows: using chlorodiphenylphosphine as starting material, chlorodiphenylphosphine and alkali metal are added to the solvent to conduct cracking, which produces a diphenyl phosphine alkali metal salt, then o-chlorobenzoic acid salt or o-chlorobenzoic acid ester is added to conduct coupling reaction to produce diphenylphosphinobenzoic acid salt or diphenylphosphinobenzoic acid ester, o-diphenylphosphinobenzoic acid is obtained after hydrolysis. o-diphenylphosphinobenzoic acid can be prepared under atmospheric pressure at temperature above 0° C. by using the present method. The method is safe and stable to operate and can save a lot of energy, thus being suitable for large-scale production.