Exploratory Reaserch On Synthesis Of Ferrocene Substituted Styrene And Furancoumarin

Transition-metal palladium catalyzed coupling reaction represent a powerful tool formodern organic synthesis and can be used to effectively build C-C and C-heteroatom bonds.Of which, palladium catalyzed Heck coupling/Sonogashira coupling reaction of unsaturatedhydrocarbons exhibit many advantages, such as mild reaction condition, high efficiency andselectivity. These methods have become one of the effective methods to introduce unsaturatedhydrocarbons and construct heterocyclic compounds, as well as an effective way to build aheterocyclic compound for the synthesis of complex natural products and drug molecules, andalso widely applied in the fields of pharmaceutical science, industry and materials. Given thefar-reaching theoretical value and practical significance of these two types of couplingreactions, a further research was made in this paper, and two kinds of ferrocenederivatives were successfully synthesized by introducing ferrocene group with a variety ofproperties in styrene and furanocoumarin compounds.In this paper, with o-iodo(bromo)phenols and vinylferrocene as substrates, ferrocenylsubstituted styrene compounds were synthesized via palladium-catalyzed Heck couplingreaction. Chosing the Heck reaction of o-iodophenol with vinylferrocene as an experimentaltemplate, the influences of varying the base, Pd-catalyst and solvent on the model reactionwere studied. The optimum reaction conditions are determined as follows:5mol%PdCl2(dppf) as catalyst, Cs2CO3as base, CH3CN as solvent, reflux6-8h under Aratmosphere. Under the optimal conditions, the Heck couplings of10different o-halophenolswith vinylferrocene were investigated and eventually obtained7different2-hydroxylphenylvinylferrocene products with the yield of52.36%-89.49%. The structures of all products werecharacterized by IR,1H NMR,13C NMR, HR-ESI-MS.In this paper, with7-hydroxyl-6(8)-halocoumarins and ethynylferrocene as substrates, ferrocene substituted furancoumarin compouds were synthesized via palladium-catalyzedSoonogashira coupling reaction. Chosing the Sonogashira reaction of7-hydroxyl-8-iodo--coumarin with ethynylferrocene as an experimental template, a full study of the effects ofvarying Pd-catalyst, base, solvent on the reaction was carried out and the optimum reactionreaction conditions are determined as follows:5mol%Pd(PPh3)4as catalyst, K2CO3as base,4mol%CuI as cocatalyst, CH3CN as solvent reflux3h under Ar atmosphere. Under theoptimum conditions, the Soonogashira couplings of8different substituted7-hydroxyl-(6)8--halocoumarin substrates with ethynylferrocene were investigated and eventually obtained8different ferrocene substituted furancoumarin products (6angle,2line) with the yield of70.29%-86.56%. The structures of all products were characterized by IR,1H NMR,13C NMR,HR-ESI-MS.