146746-35-2

Upstream product

• 141362-09-6 9-<2-(methoxymethoxy)phenyl>phenanthrene 
• 108-95-2 phenol 
• 85-01-8 phenanthrene 
• 146746-34-1 2-(methoxy)methoxyphenylmagnesium bromide 
• 824-91-9 O-methoxymethylphenol 
• 573-17-1 9-bromophenanthrene 

Downstream Products

• 43090-41-1 Naphtho<1,2,3-kl>xanthen 
• 146746-36-3 2-(phenanthren-9-yl)phenyl trifluoromethanesulfonate 

Relevant academic research and scientific papers

Synthesis of Polybenzoacenes: Annulative Dimerization of Phenylene Triflate by Twofold C?H Activation

Polycyclic aromatic hydrocarbons (PAHs) represent an emerging class of π-conjugated molecules in the area of optoelectronic devices and materials. Unprecedented synthetic routes to various PAHs from simple phenol derivatives by a palladium-catalyzed annulative dimerization of phenylene triflate through twofold inter- and intramolecular C?H activation have been established. The initially formed partially fused PAHs can be smoothly transformed into a variety of fully fused PAHs by the Scholl reaction. Furthermore, the reactions of phenanthrene-substituted aryl triflates proceeded regioselectively. The findings inspired the development of a rapid and efficient synthesis of polybenzoacene derivatives. This study not only allows transformation of phenyl triflates, but also discloses a new retrosynthetic strategy towards PAHs, especially polybenzoacenes.

Br?nsted Acid-Catalyzed Carbocyclization of 2-Alkynyl Biaryls

Ortho-alkynyl biaryls react in the presence of catalytic amount of Br?nsted acids to give phenanthrenes in high yields under mild conditions. The activity and selectivity of this transformation are governed by the substitution pattern of the diarylalkyne moiety. Selectivity shifts are observed between the carbophilic Lewis and Br?nsted acid-catalyzed cycloisomerization involving alkyne activation. (Figure presented.).

A new route to π-extended polycyclic aromatic hydrocarbons via cross-dehydrogenative coupling

A palladium-catalyzed cross-dehydrogenative coupling of phenanthrenes with simple arenes was developed. This protocol provides an opportunity for producing π-extended polycyclic aromatic hydrocarbons with minimum waste and high atomic efficiency under mild and ligand-free conditions.

Photocyclization and Photoaddition Reactions of Arylphenols via Intermediate Quinone Methides

A series of five benzannelated derivatives of 2-phenylphenol were prepared, and their photochemistry was investigated. Two of these (3-phenyl-2-naphthol, 10, and 1-phenyl-2-naphthol, 11) were photoinert. For 2-(1-naphthyl)phenol (12) and 1-(1-naphthyl)-2-naphthol (13), ESPT took place to either the 2′-position or the 7′-position of the naphthalene ring to give quinone methides (QMs) that underwent either reverse proton transfer (RPT) or electrocyclic ring closure to give dihydrobenzoxanthenes. The intermediate QMs for 12 and 13 were detected and characterized by laser flash photolysis. For 2-(9-phenanthryl)phenol (14), ESPT took place either to the 5′-position to give a QM that underwent quantitative electrocyclic ring closure to give the corresponding benzoxanthene or to the 10′-position to give a QM that underwent RPT. If the solution contained methanol, the QM produced on ESPT to the 10′-position in 14 could be trapped as the photoaddition product. The compounds studied in this work demonstrate three possible reactions of QMs produced following ESPT to aromatic carbon atoms: (1) reverse proton transfer (RPT) to regenerate starting material; (2) addition of hydroxylic solvents to give the photoaddition product; and (3) electrocyclic ring closure to give benzoxanthene derivatives.

An Intramolecular Arene-Triflate Coupling Reaction for the Regiospecific Synthesis of Substituted Benzofluoranthenes

An intramolecular triflate-arene coupling reaction mediated by bis(triphenylphosphine)palladium(II) chloride has been developed for the synthesis of each of the isomeric benzofluoranthenes.This reaction, which results in formation of a new five-membered ring, proceeds in highest yields when performed using 0.1 equiv of the palladium catalyst, 3 eqiv of lithium chloride, and 1.2 eqiv of 1,8-diazabicycloundec-7-ene in N,N-dimethylformamide at 140 deg C.The biaryl precursors needed for the coupling reaction can be prepared by nickel(II) chloride catalyzed coupling of an aryl bromide with an magnesium bromide (prepared by ortho-lithiation of an aryl methoxymethyl ether followed by transmetalation with magnesium bromide).Using this procedure benzofluoranthene, benzofluoranthene, benzofluoranthene, and benzofluoranthene were prepared in yields of 84percent, 85percent, 93percent and 64percent, respectively.The reaction to prepare benzofluoranthene was regiospecific and afforded none of the six-membered ring product, perylene.This method was extended to the preparation of benzofluoranthene (BbF) derivatives with fluoro or methoxy groups on the benzo ring.The cyclization of compounds posessing a methoxy group on the same ring as the triflate required the addition of 0.4 equiv of triphenylphosphine to the reaction mixture.Strategies are reported for the regiospecific preparation of 4-, 5-, 6-, and 7-substituted benzofluoranthenes.Evidence is presented wich suggests the intermediacy of radicals in the oxidative-addition of aryl triflates to the palladium catalyst.

A Palladium-Catalyzed Intramolecular Arene-Triflate Coupling for the Synthesis of Fluoranthrenes and Benzofluoranthrenes

A method for the preparation of fluoranthrenes and benzofluoranthrenes from aryl bromides and aryl methoxymethyl ethers is described.The key step in this synthesis is an intramolecular triflate-arene coupling mediated by bis(triphenylphosphine)palladium(II)chloride.Fluoranthrene, benzofluoranthrene, benzofluoranthrene, and indenopyrene were prepared in yields of 84-91percent.The regiospecific synthesis of substituted benzofluoranthrenes was demonstrated by the preparation of 6-fluorobenzofluoranthrene (72percent yield) and 5- and 6-methoxybenzofluoranthrene in yields of 73percent and 62percent respectively when the reaction was conducted in the presence of excess triphenylphosphine.Key Words: synthesis; palladium; triflate; fluoranthrene; benzofluoranthrene