32-Crown-10 bisphenol

Although most of the macrocycles that contain phosphorus or arsenic which have thus far been prepared, are primarily transition metals binders, two compounds have been prepared which are essentially crown ethers containing phosphorus. Kudrya, Shtepanek and Kirsanovhave prepared two compounds which are essentially polyoxygen macrocycles but which contain one or two methylphosphonic acid esters as part of the ring. These two macrocycles are shown below as 7d and 17 and are both prepared by the reaction of 2,2 [oxybis(ethyleneoxy)] bisphenolate with methylphosphonic dichloride in a mixture of acetonitrile and benzene. The crystalline monomer 16) and dimer 17) were isolated in 17% and 11% yields respectively as indicated in Eq. (6.13). 

A different variety of copolymer has been prepared by Gramain and Frere who treated 1,10-diaza-l 8-crown-6 with the bisglycidyl ether of bisphenol A. The reaction was conducted at reflux in a mixture of THF and methanol. The polymer, illustrated in Eq. (6.24) was formed 83% yield. The polymer was appparently quite stable, surviving aging tests conducted over a two-year period. 

Polymerizations were carried out using a number of bisphenols and bisthiophenols (7a-e) with HFB (see Scheme I) and with (4a-c) the bishaloaromatics (see Scheme II). Typically, solutions equimolar (ca. 2.5M) in comonomer were treated with excess anhydrous K2CO3 and 27.7 mole % of 18-crown-6 ether. Reactions were run in a number of different solvents and at temperatures from 55 to 80 . Our results showed that polymerizations were sensitive to PTC parameters such as solvent, catalyst, and trace amounts of water in the organic phase. Under optimized conditions the expected polymers were generally obtained in excellent yields and moderately high molecular weights as evidenced by ninh measurements (see Table I). 

Figure 3. Effect of water on the reaction of hexafluorobenzene and bisphenol-A in chlorobenzene in the presence of 18 crown-6 catalyst. Products of the catalyzed reaction were oligomeric materials. No reaction is observed under the experimental conditions in the absence of the 18-crown--6 catalyst. (Reproduced with permission from reference 14, Copyright 1985 John Wiley.)...

Polymerization Method. To a solution of 5.18 mmole of HFB or PFB and 5.18 mmole of the appropriate bisphenol or bisthiophenol in 20 ml of solvent was added 22.4 mmole anhydrous of K2CO3 and 1.43 mmole of 18-crown-6 ether. The magnetically stirred, heterogenous mixture was heated in an oil bath and maintained under N2. Upon cooling to room temperature, the mixture was slowly poured into ca. 150 ml of methanol and was vigorously stirred. The filtered solids were washed three times in a blender with 300-ml portions of distilled water. The solids were air dried and subsequently placed in a vacuum oven (80 ) for 24 hr. Where soluble, the polymers obtained were characterized by IR and PMR analysis. Elemental analyses for all polymers were satisfactory. Polymer solubility was determined in THF, DMF, dioxane, toluene, m-cresol, chloroform, and sulfuric acid. The percent insoluble polymer was determined gravimetrically. Inherent viscosities of soluble polymers were determined in ca. 0.5% wt. solutions in either chloroform or THF. 

Grafting of bisphenol-A polycarbonate on carbon fibers with n-BuLi in the presence of NAl,hf Al -tetramethylethylenediamine and 18-crown-6 has been reported by Drzal et al. [47]. 

Synthesis. High purity bisphenol A (Bis-A) and 4,4 -dichlorosul-fone (DCDPS) were obtained from Union Carbide. 4,4 -Thiodiphenol (Bis-T) and 4,4 -sulfonyldiphenyl (Bis-S) were supplied by Crown Zellerbach. 4,4 -Difluorodiphenylsulfone was either obtained from Aldrich or by reaction of DCDPS with anhydrous KF. 

Crown ethers were the first artificial host molecules discovered. They were accidentally found as a byproduct of an organic reaction. When Pedersen synthesized bisphenol, contaminations from impurities led to the production of a small amount of a cyclic hexaether (Fig. 2.1). This cychc compound increased the solubihty of potassium permanganate in benzene or chloroform. The solubility of this cyclic compound in methanol was enhanced in the presence of sodiiun ion. Based on the observed phenomena, Pedersen proposed that a complex structure was formed where the metal ion was trapped in a cavity created by the cychc ether. At that time, it was already known that naturally occurring ionophores such as valinomycin incorporated specific metal ions to form stable complexes because of this, compounds able to selectively include metal ions were the source of much attention from researchers. Pedersen called the cychc compound a crown ether, because the cychc host wears the ion guest like a crown. 

The technique of phase-transfer catalysis has been extensively apphed to the two-phase polycondensation using various phase-transfer catalysts, such as quaternary ammonium and phosphonium salts, crown ethers and poly(ethylene glycol)s. 5 - 53,75,87,n9,i5i Various types of condensation polymers such as aromatic polysulfonates and polysulfides, aromatic polyethers, ahphatic and aromatic polysulfides, and carbon-carbon chain polymers of high molecular weights hy the phase-transfer catalyzed polycondensation fi-om combinations of aromatic disulfonyl chlorides, phosphonic dichlorides, activated aromatic dichlorides, and aliphatic dihahdes, with bisphenol, aliphatic and aromatic dithiols, and active ethylene compounds. The two-phase polycondensation was generally carried out in a water-immiscible organic solvent-aqueous alkaline solution system at room temperature. The method of polycondensation offers a highly versatile and convenient synthetic method for a variety of condensation polymers. 

A mixture of bisphenol N,N -bis[(4-hydroxybenzylidene)- naph-thalene-l,5-diamine]l (5 mmol), (w -bromo-1-alkyl) glycidylether (10 mmol), KjCOj (25 mmol), and 18-crown-6 (0.5 mmol) in 50 mL of acetone was heated at reflux temperature for 24 h. The solvent was evaporated, and the solid was dissolved in CH Cl and... 

Since it is well known that stability of a complex between a crown ether and an alkali metal cation greatly depends on the size of the inner cavity of the former and of the latter and that of all the alkali metal ions dibenzo-18-crown-6 forms the most stable complex with K" ",27 it was interesting to see whether these facts in a parallel way influence the present polymerization reactions. We conducted a series of pol3nnerizations under the same condition as described in "Synthetic Reactions", using various alkali hydroxides (LiOH, NaOH, KOH, and CsOH) the results are tabulated in Table 2. The results strongly imply that phase transfer of the nucleophiles, bisphenolate anions, from the aqueous to the nitrobenzene phase was most efficient when the metal ion was K. This, in turn, indicates that the crown ether-K" " complex is the most stable among the complexes expected to be formed with the alkali metals examined, as has been amply demonstrated by others. For example, Pedersen ... 

Aromatic polysulfonates of high molecular weights can be prepared fi om aromatic disulfonyl chlorides and alkaline salts of bisphenols by interfacial polycondensation technique using onium salt accelerators. In the absence of the catalyst, only low molecular polysulfonate III was obtained, even though the reaction was continued for 254 hours, whereas the addition of these quaternary ammonium salts and crown ethers inereased the average molecular weight of the polymer remarkably. 

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