6639-40-3

The invention provides a method for preparing a biaryl hydrocarbon compound from an alcohol compound. The method comprises the following steps: sequentially adding the alcohol compound, sodium borohydride and iodine (the molar ratio is 1: (2-3): (0.5-1)) into a reaction tube containing acetonitrile solvent, sealing the reaction tube, heating to 100 DEG C, reacting for 10-20 hours, quenching with water after the reaction is completed, drying an organic phase with anhydrous magnesium sulfate, and carrying out rotary evaporation to remove the solvent and obtain a target product. The method has the advantages of convenience in operation, easiness in product separation, high yield, small environmental pollution and the like, is an ideal method for producing the high-energy-density hydrocarbon by utilizing oxygen-enriched biomass raw materials, and has important practical value.

A Cu-catalyzed method has been identified for selective oxidative arylation of benzylic C-H bonds with arylboronic esters. The resulting 1,1-diarylalkanes are accessed directly from inexpensive alkylarenes containing primary and secondary benzylic C-H bonds, such as toluene or ethylbenzene. All catalyst components are commercially available at low cost, and the arylboronic esters are either commercially available or easily accessible from the commercially available boronic acids. The potential utility of these methods in medicinal chemistry applications is highlighted.

A homocoupling method for organohalides and organosulfonates promoted by samarium metal and HMPA, and catalyzed by NiCl2 has been developed. Various organohalides (benzyl, aryl, heterocyclic, alkenyl and alkyl halides), α-haloacetophenones, and phenyl organosulfonates were tolerated, and the reaction afforded coupling products with high efficiency. Excellent chemoselectivity was exhibited between halides and other groups, such as ?COOH, ?NO2, halogen, heterocyclic ring, ester, and ketone groups. The stereoselectivity suggested that the reaction mechanism might involve an organosamarium species.

An unprecedented formation of benzylic sp3C–sp3C coupled dibenzylic products has been illustrated. The reactions have been carried out in the presence of three oxidizing reagents, i.e., diacetoxy-iodobenzene (IBDA), N-fluorobenzenesulfonimide (NFSI), and pyridine (Py) using toluene derivatives.

The C-C bond formation by homogeneous catalysis is a powerful tool in organic synthesis. The replacement of noble metal by cheaper one for already reported methodologies is of interest for an economical purpose. The attractivity of such replacement is also enhanced if a first raw transition metal is found to be active in several processes. This work demonstrates that a common nickel complex can be used for a two-step cross-coupling procedure, namely a homocoupling reaction of benzyl derivatives and a subsequent Suzuki reaction. These consecutive reactions permit the synthesis of new polyfunctionalized dibenzyl compounds.

(Matrix Presented) A novel palladium-catalyzed coupling reaction between two Csp3-Csp3 centers has been investigated. This protocol is initiated by the oxidative addition of an α-halo carbonyl compound to a palladium(0) species, followed by the double transmetalation. The key dialkyl palladium intermediate undergoes reductive elimination to form the desired coupling product.

Flash vacuum pyrolysis over a bed of freshly sublimed magnesium on glass wool results in efficient coupling of benzyl halides to give the corresponding bibenzyls. Where an ortho halogen substituent is present further dehalogenation gives some dihydroanthracene and anthracene. Efficient coupling is also observed for halomethylnaphthalenes and halodiphenylmethanes while chlorotriphenylmethane gives 4,4′-bis(diphenylmethyl)biphenyl. By using α,α′-dihalo-o-xylenes, benzocyclobutenes are obtained in good yield, while the isomeric α,α′-dihalo-p-xylenes give a range of high thermal stability polymers by polymerisation of the initially formed p-xylylenes. Other haloalkylbenzenes undergo largely dehydrohalogenation where this is possible, in some cases resulting in cyclisation. Deoxygenation is also observed with haloalkyl phenyl ketones to give phenylalkynes as well as other products. With simple alkyl halides there is efficient elimination of HCl or HBr to give alkenes. For aliphatic dihalides this also occurs to give dienes but there is also cyclisation to give cycloalkanes and dehalogenation with hydrogen atom transfer to give alkenes in some cases. For 5-bromopent-1-ene the products are those expected from a radical pathway but for 6-bromohex-1-ene they are clearly not. For 2,2-dichloropropane and 1,1-dichloropropane elimination of HCl occurs but for 1,1-dichlorobutane, -pentane and -hexane partial hydrolysis followed by elimination of HCl gives E, E-, E,Z- and Z,Z- isomers of the dialk-1-enyl ethers and fully assigned 13C NMR data are presented for these. With 6-chlorohex-1-yne and 7-chlorohept-1-yne there is cyclisation to give methylenecycloalkanes and -cycloalkynes. The behaviour of 1,2-dibromocyclohexane and 1,2-dichlorocyclooctane under these conditions is also examined. Various pieces of evidence are presented that suggest that these processes do not involve generation of free gas-phase radicals but rather surface-adsorbed organometallic species.

The preparation of the title compounds is greatly improved by combining seven steps (three lithiations, three substitutions and an oxidation) into a one-pot procedure. The hydrolysis of the related phosphonium salts, the lithiation of the P-propyl phosphepine oxides and their reaction with electrophiles are described.

The dissolution of a stainless steel anode provides catalytic nickel species which enable the efficient synthesis of ketones by electrolysis of organic halides in DMF in the presence of bipyridine and carbon monoxide.

The o-tolyl radicals, formed by the reaction of o-chlorotoluene with (dppe = Ph2PCH2CH2PPh2) or by the decomposition of o-toluoyl peroxide, prefrentially attack the methyl group of toluenes giving rise to bibenzyls.In contrast the m- and p-tolyl radicals preferentially attack the aromatic nucleus.

Zerovalent nickel complex generated in situ by reduction of NiBr2(PPh3)2 with zinc powder in the presence of Et4NI was found to be an effective catalyst for homo-coupling of benzyl halides.The catalytic reactions proceeded smoothly in various solvents under mild conditions to afford dehalogenative-coupling products in good to high yields.

The gas-phase pyrolysis of exo-chlorine-substituted toluenes in an atmosphere of nitrogen or hydrogen sulfide was investigated.Hydrogen sulfide stimulates the thermolysis of benzyl chloride, accelerating the formation of toluene and stilbene at 430 deg C.The other reaction products are anthracene and bibenzyl.Similar compounds and also phenanthrene are formed during the pyrolysis of benzylidene chloride in an atmosphere of nitrogen or hydrogen sulfide (500 deg C).Benzotrichloride is distinguished by its high stability; its pyrolysis mainly with the formation of 1,2-dichloro-1,2-diphenylethylene is realized at temperatures above 550 deg C.With hydrogen sulfide it reacts at 400 deg C to form bibenzyl, stilbene, anthracene, phenanthrene, and thianaphtenothianaphthene.The latter is the main product in a recirculation-type system.

Pyrolyses of a series of selenides and diselenides were studied. Selenides and diselenides bound with an active methylene group like benzyl gave a variety of substituted bibenzyls and related ethane derivatives in high yields. Other diselenides were easily caused to cleave to give various aromatic and aliphatic olefins in good yields together with elemental selenium. Lepidopterene, paracyclophane, and benzocyclobutene were prepared by thermal cleavage of their corresponding phenylselenomethyl-substituted compounds as an application of the pyrolysis concerned.

The flash vacuum pyrolysis of benzyl phenyl selenides gave bibenzyls and diphenyl diselenide in excellent yields.This type of reaction was successfully applied to the synthesis of the title compounds.

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