Preparation method of perhydrofluorene or perhydrofluorene alkyl substitute

Abstract

The invention discloses a preparation method of a perhydrofluorene or perhydrofluorene alkyl substitute.The preparation method includes following steps: (1), enabling a phenol compound or an aromatic hydrocarbon compound or an arone compound or an aromatic ether compound to be in alkylation reaction with a benzyl compound in the presence of a first catalyst to generate substituted or unsubstituted diphenylmethane, wherein the first catalyst is an acidic catalyst; (2), enabling the substituted or unsubstituted diphenylmethane to be in hydrogenation or hydrogenation and dehydrogenation reaction with hydrogen in the presence of a second catalyst to obtain the perhydrofluorene or perhydrofluorene alkyl substitute, wherein the second catalyst is a mechanical mixture of a metal catalyst and an acid catalyst or the metal catalyst loaded on the acid catalyst.

Description

technical field [0001] The invention belongs to the field of high energy density fuel synthesis and relates to a preparation method of perhydrofluorene or perhydrofluorene alkyl substitutes. Background technique [0002] High-density fuel is a synthetic liquid hydrocarbon used as fuel. In essence, it is the same as hydrocarbon fuel refined from petroleum, such as aviation kerosene JetA, rocket kerosene RP-1, etc., and can be applied to all kerosene-based fuels. Fuel for air-breathing engines and rocket engines. Compared with petroleum refining fuels, the density of high-density fuels has been greatly improved, and the mass combustion calorific value is basically the same, so it can also be called high energy density fuels, and its volume calorific value has been greatly improved. Under the condition of a certain volume of the fuel tank, more propulsion power can be provided, and the range or carrying capacity of the aircraft can be significantly improved. [0003] High-den...

AI Technical Summary

Problems solved by technology

Among them, there are two sources of fluorene: one is coal tar, and fluorene contains about 1.0-2.0% in high-temperature tar. After cooling, crystallization, and centrifugation, crude fluorene is obtained, and then industrial fluorene is dissolved in benzene, and then neutralized Washing with water, solvent removal, re-distilling fluorene, and recrystallizing the distillate with gasoline and ethanol to obtain 95% pure fluorene. This method consumes a lot of energy; the second is to generate intramolecular or Intermolecular alkylation, for example, Angewandte Chemie International Edition 2012, 51 (22), 5359-5362 uses Ru to activate the C-H of 2,2-diphenylacetic acid, and cyclizes to obtain fluorene; Angewandte Chemie International Edition 2010, 49 (16), 2909-2912 Using Ru to catalyze the cross-coupling and intramolecular cyclization of 1,2-dihalobenzene and phenylboronic acid to obtain fluorene; , 1'-biphenyl undergoes an intramolecular alkylation reaction to obtain fluorene, but this method is expensive and difficult to realize industrialization

One method of mass production of fluorene is the alkylation reaction of dichloromethane and benzene or biphenyl under the catalysis of aluminum trichloride, but this method introduces toxic benzene, and the introduced halogen is separated and recovered Difficult, high production cost, heavy environmental pollution, and the conditions for reducing fluorene derivatives are harsh and the yield is low

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