Phenoxide groups

Jacobsen s complex (la-MnCl) was also immobihzed on MCM-41 modified with phenolic groups [39]. The surface phenoxide groups act as an-... 

The long (sa 3.3A) separation would appear to be consistent with at most only one bridging 0 group between a Mn2 pair we say at most because bridging carboxylate or phenoxide groups (and no 0 ) can also result in a lengthened Mn...Mn separation. 

Bis-hydroxyphenyl-triazoles, e.g., (134), are a new class of iron chelators. They are 0,N, O-terdentate, bonding through a triazole nitrogen and two phenoxide groups their properties can be pH-tuned by (de)protonation of the carboxy substituents. ... 

More recently reported was a bridged bis(amidinate)-isopropoxy ytterbium complex 85 (Fig. 14), which displayed excellent polymerization activity in conjunction with a good control of the polymerization of L-lactide with a linear increases of polymer molecular weights (M ) with [M]o/[I]o [103]. It was also evidenced that 85 was even more active in the polymerization of lactide than its structural analog with bridging phenoxide group, as an isopropoxide is intrinsically more nucleophilic than a phenoxide. 

A few of the values were obtained indirectly from correlations with other indicators, because of either insolubility of the betaine in certain solvents or its reaction with them. Thus, the penta-t-butyl-substituted betaine on the five phenyl groups, para to their attachment to the pyridine and the phenoxide groups, is more soluble in aliphatic hydrocarbons than the standard unsubstituted betaine, that is... 

Creary, X. Wolf, A. Miller, K. Facile autoxidation of 2-(4-hydroxyphenyl)-3,3-dimethyl-methylenecyclopropane. The radical stabilizing ability of the phenoxide group. Org. Lett. 1999, 1, 1615-1618. 

A compound similar to (XIII) has also been prepared from the pyrocatechol compound Ti(02C6H4)Cl2 by reduction with sodium amalgam in THF, and has been formulated to be similar to (XIII) with the two phenoxide groups at each titanium being replaced by the pyrocatecholate dianion. The ESR signal from both these complexes suggests the presence of one unpaired electron per dimer (50). 

Further insight came from our study of other aromatic substitution reactions. When we blocked the para position of anisole in compound 65, we saw that ortho chlorination was blocked by binding with a-cyclodextrin, so the only reaction was from the substrate that was in free solution, not that which was bound. However, with p-cresol (66) there was still, of course, ortho chlorination but now it was catalyzed by the a-cyclodextrin. When p-cresol binds to the cyclodextrin, the polar phenol or phenoxide group will be out of the cavity, bringing the ortho positions within reach of the cyclo-... 

Phenoxide group displacement by a hydride or a deuteride takes place in the case of the dibenzofuran complex. Indeed, on treating the dibenzofuran complex 89 with LiEt3BD, ring-... 

Cp = concentration of all phenoxide functional groups CPi = concentration of monomeric phenoxide groups Cp2 = concentration of phenoxide groups on chain ends... 

A factor of 2 is introduced into Equation 5 since the reaction of one monomeric phenoxide group causes the adjoining phenoxide to become a chain-ended phenoxide. This also explains the presence of the term, kiCpiCc, in Equation 6. By adding Equations 5 and 6, we obtain an equation for the total phenoxide reaction rate ... 

Partially substituted compounds like [Tia2(OPh)2]2 and [(EtO)3Ti(glycinate)]235 have bridging phenoxide groups but with bulky aryloxides a variety of different types may be formed.36... 

This approach is based on the condensation of o-aminophenol with picryl chloride, originally reported by Turpin in 1891.14 The mechanism consists in an intramolecular nucleophilic displacement of the nitro group from a suitably substituted 2-hydroxy-2 -nitrodiphenyl-amine (5) by the phenoxide group in alkaline medium. 

A terminal cyclic urea derivative of valine is present at one terminus in lopinavir (43). Preparation of this heterocyclic moiety begins with conversion of valine (35) to its phenoxycarbonyl derivative by reaction with the corresponding acid chloride. Alkylation of the amide nitrogen with 3-chloropropylamine in the presence of base under very carefully controlled pH results in displacement of the phenoxide group to give the... 

When phenyl tellurium trichloride or 4-phenoxyphenyl tellurium trichloride were reacted with sodium 2-benzoyl-5-methoxyphenoxide in a refluxing mixture of benzene/methanol, compounds were obtained that contained chloride and phenoxide groups. ... 

Reactions of amines with substituted phenyl acetates are subject to a change in pathway as a function of basicity of the leaving phenoxide group. In the ammonolysis, hydrazinolysis, and imidazole-catalyzed hydrolysis of substituted phenyl acetates, both first- and second-order terms in amine are observed (Bruice and Mayahi, 1960 Bruice and Benkovic, 1964). Out of five phenyl acetate derivatives (p-NOg, m-N02, p-H, p-Cl, and p-CHs) the general-base term kz is observed with only the least acidic leaving groups, that is p-CHs, p-H, and p-Cl in the case of ammonolysis and hydrazinolysis, and p-CHj in the case of the imidazole reaction. Uncatalyzed k terms are observed with all... 

Immediately after the deprotonation from s w-zn-hydroxyphenyl-l, 2-dioxetane, the charge on 0(14)-C6H( is 0.53e and 0(3)-CH is 0.27e.. The HOMO at A in Fig.3 shows that both the a -HOMO and 0 -HOMO are on the phenoxide group. When the reaction proceeds to the transition state B, an electron is transferred to the 03-04 a orbital (anti-bonding) as shown in P -HOMO of B in Fig.3. Going down the potential curve the... 

C. The reaction proceeds to the point D, the 0-MO and the a-MO show that an electron transfer occurrs from the phenoxide group to the Cl-03 n orbital. Furthermore at the point E the a -MO shows involvement of the excitation at 04. This... 

In another example of a dendrimer with a metal cluster core, Gorman and co-workers reported that dendritic ligands with phenoxide groups substituted for triflate or methoxide ligands around an Mo6C18 core to form molecules of the type Mo6(jjl3-C1)8(OR)6, where R = dendrons with zero to two hyperbranches.53... 

Polymerization. Typically, the dihydric phenol (1 mole) and aqueous alkali metal hydroxide (2 moles) are mixed under an inert atmosphere in sulfolane and benzene. The water from the aqueous solution plus metal phenoxide formation is removed by distillation of a benzene-water azeotrope between 110° and 140°C. After water removal has been completed, the excess benzene is distilled off, the anhydrous salt in sulfolane cooled to 70°-80°C, and bis(4-chlorophenyl)-sulfone (I) added. The temperature is increased gradually to 200°C and held for four to five hours. Methyl chloride is bubbled in at the end of the polymerization to convert any terminal phenoxide groups to methyl ethers (10). 

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