Diphenol methyl ethers

Stoddart and coworkers reported that a macrocyclic bisviologen acceptor (28) acts as a versatile host for -electron rich systems, such as diphenol methyl ethers, dinaphthol methyl ethers, and aromatic amino acids [99-102]. They also discovered that TTF (2) and 28 form a 1 1 complex in which... 

The synthesis of a diphenylmethano-bridged fuUerene derivahve with reactive functional groups on the phenyl rings is exemplified by the preparahon of the diphenol derivative 118 (Scheme 4.23). It can be obtained from the corresponding methyl ether by treatment with BBrj in o-dichlorobenzene at 0 °C to room temperature in 94% yield. In contrast to the non-polar diphenyl-methano bridged fullerenes, 118 is soluble and stable in pyridine but sparingly soluble in benzene or toluene. 

The reaction of ( + )-bulbocapnine methyl ether (42) with excess boron trichloride in methylene chloride containing 0.3% ethanol produces the catechol (43) together with the monophenol (44). However, with boron tribromide, it is the diphenol (45) which is produced. Both compounds (44) and (45) can be O-methylated with diazomethane to the dimethyl ether (46), and hydrolysis of (46) with dilute hydrochloric acid leads to (+)-corytuberine (47).43 Alternatively, methylation of (43), using diazomethane, affords (+)-corydine methyl ether (48). 

Coniferyl Alcohol.—If two hydroxyl groups are present in the ring and one in the side chain we will have a mixed diphenol and aromatic alcohol. Such an alcohol, in which one phenol hydroxyl is in the form of a methyl ether, and the side chain is the propenol unsaturated chain, is known as coniferyl alcohol. 

Biomimetic syntheses of dibenzoazonines 635 and 636 were carried out by VOF3-mediated oxidation of diphenolic benzylisoquinoline 637 and its methyl ether 638, respectively. The diphenolic compound 637 was submitted to VOF3-mediated oxidation at — 10°C to afford in 40% yield the para-para coupled spirodienone 639, which was further converted to dibenzoazonine 635 (Scheme 122) ". Similar coupling reactions have also been carried out . ... 

Although diphenols have not yet been coupled electrochemically, their methyl ethers have recently been coupled with considerable success. Yields have been high, and the reactions seem remarkably clean. Oxidation of the hydrochloride of 102 was carried out on a graphite anode in water using tetraethylammonium perchlorate as the electrolyte. Potentials were controlled at 0.7 V. The dienone 103 was obtained in 23% yield (57). Similar anodic oxidation of 94a gave the homoaporphine 100a 58). 

The structure of this base and some of its congeners was proved by exhaustive spectral data as well as by a synthesis. The diphenol LXXII (R = OMe) prepared by standard procedures was oxidized by alkaline ferricyanide to LXXIII (R = OMe) which is thus a ring homologue of the proaporphines. This product rearranged in concentrated sulfuric acid to yield LXXIV (R = R2 = R4 = H, R = OMe, R = Me), methylation of which with diazomethane gave a mixture of ( )-kreysigine (LXXIV R = R = H, Ri = OMe, R2 = RS = ] Je) and its 0-methyl ether. Deacetyl-colchicine was also found in the plant from which these alkaloids were isolated (114). Shortly after the above was reported there appeared a... 

In ethanol-free methylene chloride, bulbocapnine methyl ether (30) with boron tribromide affords a mixture of diphenol 33 and phenanthrene 35. 

The presence of a little ethanol in the solvent leads, upon the addition of boron tribromide, to some hydrobromic acid resulting in formation of the hydrobromide salt of the initial aporphine. No phenanthrene is ultimately obtained under these conditions. Bonding of boron tribromide to the basic nitrogen seems to be the initial step in the opening of ring B. This is supported by the observation that reaction of (-f-)-bulbocapnine methyl ether (30) with boron tribromide in the presence of a strong base such as l,8-bis(dimethylamino)-naphthalene furnishes mainly the phenanthrene derivative 35. On the other hand, the hydrobromide salt of 30 when treated with boron tribromide produces only the diphenol 33. ... 

Synthesis. Five different polyaryl ethers were made from the condensation product, resulting from the reaction of phenol and levulinic acid, commonly referred to as diphenolic acid, and one or more of the following monomers bisphenol A, dichlorodiphenyl sulfone, 2,6-dichloro-benzonitrile, and 4,4 -difluorobenzophenone. The resulting polymers were subsequently methylated such that the common monomer becomes (1) ... 

A fluorinated poly(arylene ether sulfide) (PSI) is prepared from the condensation of bis-(pentafluorophenyl)-sulfide with 4,4 -(trifluoromethylphenyl-isopropyhdene)diphenol, which is a methyl fluorinated bisphenol A. " ... 

Researchers at DnPont used hydroquinone as5mimetrically substituted with chloro, methyl, or phenyl substituents and swivel or nonlinear bent substituted phenyl molecnles such as 3,4- or 4,4 -disubstituted diphenyl ether, sulfide, or ketone monomers. For example, poly(chloro-l,4-phenylene- ra/ s-hexahydroterephthalate) and related copolymers were prepared in a melt-polymerization process involving the reaction of molar equivalents of the diacetoxy derivatives of diphenols and hexahydroterephthalic acid (19). During polymerization, a phase transition from isotropic to anisotropic occurred soon after the rapid melting of the intermediates to form a clear, colorless liquid. 

Structural studies of polymer surfaces. Materials that have been studied include PMMA [239], PMMA-polypyrrole composites [240], polyfchloromethyl styrene) honnd 1,4,8,11-tetrazacyclotetradecane, polyfchloromethyl styrene) honnd thenoyl triflnoroacetone [241], poly(dimethyl siloxane)-polyamide copolymers [242], PS [243], ion-implanted PE [244], monoazido-terminated polyethylene oxide [245], polynrethanes [246], polyaniline [247], flnorinated polymer films [248], poly(o-tolnidine) [249], polyetherimide and poly benzimidazole [250], polyfnllerene palladinm [251], imidazole-containing imidazolylethyl maleamic acid-octadecyl vinyl ether copolymer [252], polyphenylene vinylene ether [253], thiophene oligomers [254], flnorinated styrene-isoprene derivative of a methyl methacrylate-hydroxyethyl methacrylate copolymer [255], polythiophene [256], dibromoalkane-hexaflnorisopropylidene diphenol and bisphenol A [257], and geopolymers [258]. 

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