Methoxybiphenyl

Phenylanisole (4-methoxybiphenyl) [361-37-6] M 184.2, m 89.9-90.1". Crystd from benzene/pet ether. Dried under vacuum in an Abderhalden pistol. 

General procedure for Suzuki coupling. 4-Bromoanisole (125 pL, 1 mmol), phenylboronic acid (186 mg, 1.5 mmol), K2CO3 (0.55 g, 4 mmol) and the BaCei.j,Pdj,03.j, catalyst were mixed in a 20 ruL scintillation vial. A preheated 2-propanol/water solution (IPA/H2O, 1 1 v/v, 12 ruL, 80°C) was added, the vial was immediately placed on a hot plate stirrer and its temperature was maintained at (80 1) °C. The reaction mixture was stirred at 1000 rpm for 3 min, then cooled to room temperature. The 4-methoxybiphenyl product was extracted with diethyl ether (3 x 15 ruL). The organic fractions were washed with deionized water and dried with MgS04. After filtration, volatiles were removed under reduced pressure to yield the isolated product. 

Poly(epichlorohydrin) (PECH) and poly(2,6 - dimethyl-1,4-phenylene oxide) (PPO) containing pendant mesogenic units separated form the main chain through spacers of zero to ten methylene units were synthesized and characterized in order to test the "spacer concept." Both polymers were modified by phase transfer catalyzed esterifications of the chloromethyl groups (PECH) or the bromobenzyl groups (brominated PPO) with potassium co -(4-oxybiphenyl) alkanoates and potassium u-(4-methoxy-4-oxybiphenyl)-alk.an oates. While PPO required ten methylene units as a spacer and 4,4 -methoxybiphenyl as mesogen to present thermotropic liquid crystalline mesomorphism,... 

Special mention has to be made of the use of surfactants. Aryl halides are insoluble in water but can be solubilized in the aqueous phase with the aid of detergents. A thorough study [24,25] established that the two-phase reaction of 4-iodoanisole with phenylboronic acid (toluene/ethanol/water 1/1/1 v/v/v), catalyzed by [PdCl2 Ph2P(CH2)4S03K 2], was substantially accelerated by various amphiphiles. Under comparable conditions the use of CTAB led to a 99 % yield of 4-methoxybiphenyl, while 92 % and 88 % yields were observed with SDS and n-Bu4NBr, respectively (for the amphiphiles see Scheme 3.11). Similar effects were observed with Pd-complexes of other water-soluble phosphines (TPPTS and TPPMS), too. 

Naphthalenes biphenyls.3 The reaction of 1,3-diphenylacetone (1) with DMF dimethyl acetal at 110° affords the bisenamine 2 when conducted at 180° the reaction results in a naphthalene derivative (3) (equation I). This synthesis of naphthalenes is general and yields are usually 50-90%. The same reaction when applied to 4 results in a 4-methoxybiphenyl derivative (5) (equation II). When the carbonyl group in 1 is labeled with 13C, it can be identified as the carboxyl group in the carboxamide 3. Thus an extensive rearrangement is involved. 

DCV kinetic data for the coupling reactions of the 4-methoxybiphenyl cation radical in acetonitrile ... 

Note. (1) The 4-chlorobenzenediazonium fluoroborate may be prepared using the conditions described for p-methoxybenzenediazonium fluoroborate, Expt 6.77, p-fluoroanisole. This methoxy derivative could also be used in the above preparation to give 4-methoxybiphenyl, m.p. 89 °C. 

Name 4 -Methoxybiphenyl-4,4-[(allyloxy)phenyl] benzoate Structure ... 

Alkoxy derivatives of biphenyl can be obtained either from alkoxy-anilines or by coupling with alkoxybenzenes. From diazotized p-bromo-aniline and anisole a 20% yield of 4-bromo-2 -methoxybiphenyl and a 7% yield of 4-bromo-4 -methoxybiphenyl are obtained. In connection with their studies on Cannabis Indica, Ghosh, Pascall, and Todd u prepared the highly substituted biphenyl compound, 2-cyano-5-methyl-2, 5 -dimethoxy-4 -n-amylbiphenyl (VII), in 27% yield from the nitrosoacetyl derivative of 2-cyano-5-methylaniline and 2,5-dimethoxy-n-amylben-zene. 

SCHEME 51. Immobilization of 4-methoxybiphenyl to Argogel and release of the products by electrophilic degermylation... 

Pentachloro-4-methoxybiphenyl tris(2,4,6-trichlorophenyl) methyl radical... 

Biphenyl mesogens with R=CN [(4 -cyanobiphenyl-4-yl-)oxy-] or R=OCH3 [(4 -methoxybiphenyl-4-yl)-oxy-] were attached to norborn-2-ene moieties, and separated by different spacer lengths and carboxylic acid ester, ether or imido-groups as anchoring moieties, as shown in Fig. 4. 

Another set of polymers were synthesized from ( )-exo,endo-his[to- 4 -methoxybiphenyl-4-yloxy)alkyl]bicyclo[2.2.1]-hept-5-ene-2,3-dicarboxylates. 

Also, N,N -di-n-dodecylcarbodiimide (76 % yield), N-6-(4 -methoxybiphenyl-4-oxyhexyl-N -n-hexylcarbodiimide (60 % yield) andN-6-(4-methoxyphenylazo)phenyloxy)hexyl-N -n-hexylcarbodiimide (70 % yield), monomers for liquid crystalline polyguanidines, are synthesized in the same manner. ... 

This discussion of electrodimerization will be concluded with another radical cation example. The anodic coupling of 4-methoxybiphenyl has been obseryed to give good yields of the dimer, 4,4" -dimethoxyquaterphenyl [16]... 

Kinetic analysis of the coupling of 4-methoxybiphenyl radical cation"... 

The reaction of n radical cations with n nucleophiles usually leads to C-C bond formation, a reaction that can be very fast (cf. pericyclic reactions also), as in the oxidative dimerization of triphenylamine k = 1-10 x 10 M s ) [293], Hence, such a reaction mechanism can even operate in anodic oxidations (4-methoxybiphenyl [294], tetrahydrocarbazole [295], 4,4 -dimethoxystilbene [296] and 9-methoxyanthracene) [297], where the radical cation concentration is very high. 

Aryl methyl ketones give generally high yields of acids on treatment with hypohalites [6SS, 696,698, 736. The reaction of 1,3,5-triacetylbenzene and sodium hypochlorite results in a 94% yield of trimesic acid [655], and that of methyl p-naphthyl ketone and sodium hypochlorite gives an 87-88% yield of p-naphthoic acid [695]. 4-Acetyl-4 -methoxybiphenyl is converted... 

The hydrogen storage alloy (1) [10], 4-methoxybiphenyl (2b) [11] and 2-phenylpyridine, (7) [12] were prepared by the method reported previously. Other reagents were commercially available and were purified by recrystallization or distillation prior to use. H-and C-NMR spectra were recorded on a lEOL JNM-GSX-400 spectrometer as a CDCI3 (for H and C-Nl ) or CHCI3 (for H-NMR) solution. MS spectra were obtained with a JEOL JMS-DX-303 spectrometer. 

Typical procedure. A mixture of di(p-methoxy)phenyltelluride (684 mg, 2 mmol) P(pyrro)3 (579 mg, 2.4 mmol) and Ni(PEt3)4 (106 mg, 0.2 mmol) in acetonitrile (5 ml.) was heated at 80°C overnight (20 h). The reaction mixture was poured into 10 mL of 1 M HCl to liberate metallic tellurium instantly. Extraction using CHjClj, drying over MgS04 and concentration afforded the crude product, which was subsequently passed through a short silica gel column (ethyl acetate/chloroform/hexane = 0.5 l 8) to give pure 4,4-methoxybiphenyl as a white solid (394 mg, 1.84 mmol, 92%). 

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