Phenoxy group

Tiiiman N, Uiman A, Schiidkraut J S and Penner T L 1988 incorporation of phenoxy groups in seif-assembied monoiayers of trichiorosiiane derivatives—effects on fiim thickness, wettabiiity, and moiecuiar-orientation J. Am. Chem. Soc. 110 6136-44... 

Cl Disperse Violet 26 is prepared by the reaction of l,4-diamino-2,3-dichloroanthraquinone (Cl Disperse Violet 28 (35)) with potassium phenoxide in phenol as a solvent at high temperature. Introduction of phenoxy groups into the 2,3-position shifts the shade to bright, reddish violet and improves the lightfastness and sublimation resistance. 

In 2-substituted dinitrothiophenes, phenylsulfone and p-nitro-phenoxy groups both react faster than the chloro group with pyridine, i.e., in a reverse order with respect to l-substituted-2,4-dinitro-benzenes, although with both substrates the factors involved are small. 

Aryloxy, hydroxy arylsulfonyloxy, and phosphoryloxy. The 4-toluenesulfonyloxy and 4-nitrophenyloxy groups approximate the chloro group in replaceability in benzene derivatives. The former appears to be less reactive than chloro toward hydroxide on quinoline and -phenoxy on pyrimidine is relatively unreactive toward sulfanilamide anion or ammonia. On cinnoline, quinazoline, or quinoline, a 4-phenoxy group is less reactive than a chloro group. 

The relatively poor resonance activation of the 2-Le-3-aza orientation in bicyclics (cf. Section IV, A) is illustrated by nucleophilic substitutions below. Vigorous conditions are required for methoxylation (110°, 17 hr, quantitative yield) of 3-bromocinnoline and for amination (aqueous ammonia, copper sulfate, 20 hr, high yield) of 3-bromo- (at 130°) or of 3-chloro-derivatives (at 165°). 3,4-Dichlorocinnoline gives predominantly 4-substitution in hydra-zination (90% yield, 20°, 4 days in alcohol), amination (70% yield, 150°, 22 hr in alcohol), and hydroxylation (50% yield, 150°, 22 hr, aqueous ammonia). The poorer-leaving phenoxy group in 3-chloro-4-phenoxycinnoline, is displaced with ammonium acetate (160°, few mins, 60% yield). ... 

If we consider the LOI values reported in Table 8, it can be clearly seen that the flame resistance of polyphosphazenes is very high and can reach values above 60 when halogenated phenoxy groups (e.g. 4-bromophenoxy) are attached to the polymer chain. However, enhancement of the carbon content in the materials (i.e. by increasing the percentage of organic substituents in the chain) induces a concurrent decrease in the flame resistance of POPs, which can be depressed to 23.4 in the case of poly[bis(4-/sopropylphenoxy)phos-phazene]. 

Trifluoroethoxy and phenoxy groups are hydrophobic. The methylamino group is hydrophilic. Studies have been made of the effect on surface properties and semipermeabiUty of variations in... 

Methoxyphenyl (PMP) ethers find occasional use as hydroxy protecting groups. Unlike benzylic groups, they cannot be made directly from the alcohol. Instead, the phenoxy group must be introduced by a nucleophilic substitution.185 Mitsunobu conditions are frequently used.186 The PMP group can be cleaved by oxidation with CAN. 

Magnesium phenolates react with triethylorthoformate regiospecifically at the ortho position of the phenoxy group (normally phenols give alkyl ethers) giving diarylmethanes. This reaction is complex and the product composition depends on the phenol and the reaction conditions.52... 

The most surprising observation from low temperature reactions was the formation of adducts between good donor solvents (Tetralin, octahydrophenanthrene, tetrahydroquinoline) and acceptor radicals. The resulting adducts were not of a single predominant structure. In particular, several isomers of toluene-Tetralin were formed as well as di-Tetralin. Several of these reactions were done with D -Tetralin which permitted the firm identification of the Tetralin moiety in the adducts. GLC-MS studies indicated that the Tetralin may be bonded to phenyl, benzyl, benzyloxy- or phenoxy-groups, depending on the acceptor used. 

The hybrid polymer 140 is generated by a thermal ring-opening polymerization (ROP) process (Scheme 10).300,301 Polymers containing three-coordinate sul-fur(IV) are generally hydrolytically sensitive even when the chloro substituents are replaced by phenoxy groups.302... 

Metabolism of the 2,S -isomers proceeds sequentially hydroxylation at the phenoxy group, hydrolysis of the cyano group, and cleavage of the ester linkage (Coats et al. 1989). Fenvalerate and the IS-isomers yield two ester metabolites in feces from hydroxylation at the 4 - and 2 -phenoxy positions. Other significant metabolites were 3-phenoxybenzoic acid and its hydroxy derivatives from the alcohol moiety, 3-(4-chlorophenyl) isovaleric acid and its hydroxy derivatives from the acid moiety, and thiocyanate and carbon dioxide from the cyano moiety (Ohkawa et al. 1979). A slow elimination rate characterizes fenvalerate and other a-cyano pyrethroids when compared with... 

Some other nucleophilic substitutions have also been reported involving these which implied the substitution of chloro, methylsulfanyl, methylsulfonyl, and phenoxy groups by phenoxy, amino, or hydrazine substituents. These reactions are summarized in Table 2. 

Example 7 the bis(2,4-dinitrophenyl)phosphoroamidite which can be prepared by a standard procedure reacts with alcohols in a non-selective way which leads to a mixture of products [28]. From a mechanistic point of view this result is consistent with spontaneous displacement of a 2,4-dinitro-phenoxy group in the reaction with alcohol which liberates free DNP. The latter activates the amino group allowing further ligand exchange. However if phosphitylation by the bis(2,4-dinitrophenyl)phosphoroamidite is performed in the presence of one equivalent of triethylamine, high chemoselec-tivity is observed, and the nucleoside (2,4-dinitrophenyl)phosphoramidite is formed in over 92% yield. 

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