Aniline alkoxy derivatives

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. 

A similar procedure can be used in the diazotization of homologs and alkoxy derivatives of aniline, m-halogen derivatives of these, polynuclear bases such as benzidine, diaminodi- and -triphenylmethanes, di-aminodiphenylether, etc., and their derivatives, and, in general, for all amines of the benzene series whose hydrochlorides are not decomposed by water. Aminosulfonic and carboxylic acids can also be diazotized by the above procedure if they are sufficiently soluble in dilute hydrochloric acid. 

Alkoxy derivatives of aniline are manufactured for use in dye and pharmaceutical production. Thus the action of methanol and sodium hydroxide on o-chloronitrobenzene, followed by reduction, yields o-anisidine (o-methoxyaniline) (24a). The para-isomer 24b is prepared in a similar way. Both are used for azo dyes and azoic intermediates. The ethoxy derivatives, o-phenetidinc (24c) and p-phenetidine (24d), are used in dye manufacture. The amine 24d is also used to make Phenacetin (acetophenetidine) (25). 

Hydrogenation of aryl amines. Rhodium-alumina appears to be the catalyst of choice for the low-temperature hydrogenation of anilines, particularly alkoxy derivatives, to cyclohexylamines. " Hydrogenolysis is not extensive, and usually secondary amines are formed in only small amounts. 

Among the most common P(ANi) derivatives studied thus far are the alkyl and alkoxy derivatives, primarily OAtto-substituted, e.g. f)-toluidine and o-methoxy aniline. Their syntheses from monomer are very similar to that of P(ANi), and in nearly all cases, they have been found to have conductivity, processibility and other properties poorer than that of P(ANi). Gopal et al. [44] have even described a A-(2-methoxy)-ethoxy derivative, which has a maximum conductivity of ca. 4 X 10 S/cm. Their electrochemical, spectroelectrochemical and spectral properties are predictable based on those of P(ANi), and do not shed additional light on the properties of P(ANi). From a practical aspect, therefore, these derivatives are largely of scientific interest only, to demonstrate that derivatives of P(ANi) can be synthesized. 

The products are (220), probably formed by the dimerization of (219), and the 2-alkoxy-l,2-thiaphosphole derivatives (218). Analogues of the latter are obtained with p-toluenethiol and dialkylamines. The compound (217 R=Ph) is more reactive than (217 R Me ) and will react with aniline on addition of triethylamine even at room temperature, from which the formation of (221) was observed by spectroscopic characterization. Even more reactive is cyclohexylamine which furnishes an analogue of (221) without addition of strong base. ... 

A striking feature of disperse dye development in recent decades has been the steady growth in bathochromic azo blue dyes to replace the tinctorially weaker and more costly anthraquinone blues. One approach is represented by heavily nuclei-substituted derivatives of N,N-disubstituted 4-aminoazobenzenes, in which electron donor groups (e.g. 2-acylamino-5-alkoxy) are introduced into the aniline coupler residue and acceptor groups (acetyl, cyano or nitro) into the 2,4,6-positions of the diazo component. A PPP-MO study of the mobility of substituent configurations in such systems demonstrated that coplanarity of the two aryl rings could only be maintained if at least one of the 2,6-substituents was cyano. Thus much commercial research effort was directed towards these more bathochromic o-cyano-substituted dyes. 

Many organic chemicals are analyzed by RPC. These include various arylhydroxylamines as the N-hydroxyurea derivative with methyl isocyanate (614) alkyl- and alkoxy-disubstituted azoxybenzenes (6t5), n-alkyl-4-nitrophenylcarbonate esters ranging in length from methyl to octyl (616), 4-nitrophenol in the presence of 4-nitrophenyl phosphate (617), ben-zilic acid, and benactyzine-HCI using ion-pair chromatography (618), as well as aniline and its various metabolites (619), stereoisomers of 4,4 -dihydroxyhydrobenzoin (620), and aldehydes and ketones as the 2,4-dinitrophenylhydrazones (621). The technique has also been used to analyze propellants and hydrazine and 1,1-dimethylhydrazine were quantitita-vely determined (622, 623). 

Boron trifluoride etherate was used in conjunction with the reducing agent borane to rearrange aromatic O-triisopropylsilyl ketoximes to cyclic and acyclic aniline derivatives. The steric hindrance of the substituents on the silicon atom, the size of the aliphatic ring and the presence of alkoxy substituents on the aryl group played important roles in the aniline formation. 

The addition of anilines to styrene oxide was reported to also proceed in the presence of 10mol% 37 affording the corresponding P-amino alcohols 1-5 in yields ranging from 75% to 92% (Scheme 6.37). Additionally, urea derivative 37 (20mol% loading) was found to catalyze the addition of aniline (2.0 equiv.) to ( )-stilbene oxide (92% yield 5.9 d 30°C), the addition of thiophenol (2.0 equiv.) to 2-methoxy styrene oxide (85% 20h rt), and the alcoholysis of 4-methoxy styrene oxide with benzyl alcohol (2.0 equiv.) affording the respective P-alkoxy alcohol (82% 20h rt). 

Electropolymerization in acidic media affords free-standing films that are believed to contain varying degrees of cross-linking [267,292,304]. The miscibility of aniline with water allows for a variety of aqueous oxidants, such as ammonium peroxydisulfate, to be used [305]. Chemical polymerization of aniline can also be performed in chloroform through the use of tetrabutyl ammonium periodate [306]. Accordingly, a number of alkyl [301] and alkoxy-substituted [307] aniline derivatives have been chemically polymerized. Unfortunately, functionalization of the aniline nucleus often leads to a decrease in performance in the resulting polymers [308,309]. 

Compounds with Reactive Methylene Groups. In this group the coupling components with the greatest industrial importance are the A-acetoacetyl derivatives of aromatic amines (acetoacetarylides) CH3COCH2CONHAr. Anilines substituted by halogen, alkyl, alkoxy, nitro, and acylamino groups are most suitable (e.g., Napthol AS-IRG). 

The etherification of phosphonitrilechlorides with alcohols, phenols and naphthols can produce various alkoxy, phenoxy- and naphthyloxyderiva-tives of phosphonitrilechlorides the interaction of these derivatives with amines or aniline yields various phosphonitrilamines and phosphonitrie-lanylide. 

Due to the attractivity of this method several groups have developed onium salt supported versions of classical reactions. For example, starting from hydroxyl derived imidazolium salts, formation of supported acrylates with acryloyl chloride followed by reaction with diene in refluxing toluene afforded Diels Alder adduct in good yields (>65%). After saponification, products are isolated without further purification [127], Alternatively, starting from carboxylic acid derived imidazolium salts, acyl chloride formation with thionyl chloride in acetonitrile, followed by reaction with 4-aminophenol led to supported N-arylamide. Williamson alkylation using NaOH as a base and subsequent cleavage from the onium salt support under acidic condition (HCI/I I2()/ AcOH) allowed for isolation of various alkoxy substituted anilines with >98% purity... 

Ghedini has studied a series of salicylaldimato palladium(II) complexes with chiral alkoxy chains on the anilinic portion of the molecule. When the chain is derived from S-(—)- 8-citronellol then enantiotopic S and Sc phases are observed, whereas using i -(-)-2-octanol yields a complex displaying a monotropic N phase... 

There are a few alkoxy " or trimethylsilyloxy butadienes which react with the Vilsmeier reagent to give formylated products in moderate yields (Eqs. 49 and 50). In the latter case the products are isolated as aniline derivatives 57. 

The condensation reaction of aniline with alkoxy-methylenemalonic esters, followed by cyclization to 4-hydroxy-3-carbalkoxy quinolines, is described as the Gould-Jacobs reaction. The reaction can use various derivatives of methylene malonic ester such as keto-malonic esters, malonitriles, malonamides, and Meldrum acid. 

The basic method of synthesizing derivatives of dihydroquinoline is condensation of aniline [70, 266-268] and its p-allg l- [269], alkoxy- [270, 271], mono- and di-alkylamines [269] with the corresponding aliphatic aldehydes and ketones in the presence of catalysts (HCl, H2SO4, iodine, bromine, aromatic sulfonic acids, etc.) ... 

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