Quat salts

Normally the reaction Is useful for the conversion of alkyl halides to primary amines without concomitant formation of secondary amines.29 Treatment of polymer 17 with hexamethylenetetramine in a mixture of ethanol/THF afforded an insoluble resin. Using diazabicyclooctane (DABCO), we demonstrated that the reaction could be limited to attack by a single nitrogen in a multifunctional amine, so we did not anticipate crosslinking via bis-quat salt formation. Hydrolysis of 2 with anhydrous HC1 in ethanol generated free amino groups as evidenced by a positive ninhydrin test, but quantitative hydrolysis could not be achieved and the product remained insoluble. One would have expected a simple bis-quat to hydrolyse and open the crosslinked structure. 

Polymerization of butyl acrylate was also studied by us in ethyl acetate/water two phase systems (3) using potassium persulfate/quaternary ammonium salts as the initiator system. Under these conditions (a minimum amount of water was used to dissolve the persulfate), it was found that symmetrical quat salts were more efficient than surfactant type quat salts. Also, the more lipophilic quat salts were more efficient. These results prompted us to propose formation of an organic-soluble quaternary ammonium persulfate via typical phase transfer processes. 

With respect to [HPC], it was observed that although the rate of polymerization increased with increasing quat salt concentration, be a tendency for the rate to level approached that of the persulfate, the data, however, are nearly linear [HPC] at 60 ... 

Case 1 appears to accurately predict the observed dependence on persulfate concentration. Furthermore, as [Q]+otal approaches [KX], the polymerization rate tends to become independent of quat salt concentration, thus qualitatively explaining the relative insensitivity to [Aliquat 336]. The major problem lies in explaining the observed dependency on [MMA]. There are a number of circumstances in free radical polymerizations under which the order in monomer concentration becomes >1 (18). This may occur, for example, if the rate of initiation is dependent upon monomer concentration. A particular case of this type occurs when the initiator efficiency varies directly with [M], leading to Rp a [M]. Such a situation may exist under our polymerization conditions. In earlier studies on the decomposition of aqueous solutions of potassium persulfate in the presence of 18-crown-6 we showed (19) that the crown entered into redox reactions with persulfate (Scheme 3). Crematy (16) has postulated similar reactions with quat salts. Competition between MMA and the quat salt thus could influence the initiation rate. In addition, increases in solution polarity with increasing [MMA] are expected to exert some, although perhaps minor, effect on Rp. Further studies are obviously necessary to fully understand these polymerization systems. 

Achlorophenacyl bromide [536-38-9] aC6H4COCH2Br 96-96.5 13518 1.647 prep quat salts of methenamine, chlorophenol glyoximes, corrosive la.chrima.tor 162... 

Two routes of catalyst decomposition are also possible from alkoxide 29, fragmentation to form an epoxide or O-alkylation and subsequent fragmentation to an enol ether. Both of these tertiary amines can then be IV-alkylated to form new chiral, non-racemic quat salts. The quaternary ammonium catalyst can also be dequatemarized by nucleophiles to a tertiary amine, which can then undergo subsequent reactions [9c, 1 li,26b,87]. 

The addition sequence quat salt, caustic solution, pretreat-ment, then reagent is critical Addition of quat salts to caustic pretreated cellulose does not produce a significant enhancement of the extent of substitution. Similarly, addition of tertiary amines assuming that the corresponding quaternary salt of the reagent will be produced in situ is ineffective. Treatment of native cellulose with tetramethylammonium hydroxide alone did not produce an activated substrate. 

The extent of substitution obtained after 2-2.5 hours reaction time is reported in Table I. The pretreatment conditions influence the relative effectiveness of the quat salt, but comparisons within a given pretreatment are valid. 

Selection of appropriate quaternary ammonium catalysts is limited by their stability in the reaction medium. The cellulose pretreatment requires heating in strong caustic solutions up to 120 most tetraalkyl ammonium salts undergo Hoffman degradation under these conditions. We have found two relatively stable quat salts, tetramethylammonium chloride and N,N-dimethylmorpholinium... 

We have shown that the efficiency of the catalyst decreases when the water content of the cellulose increases, so dilution of the catalyst solution is counterproductive. Addition of other diluents such as butanol to the system reduced catalyst activity and tended to promote more by-product formation. Thus, it was not feasible to disperse the more hydrophobic quat salts efficiently in organic solvents. Experimental difficulties aside, however, TMAC is uniquely effective in actvating cellulose in a dry blend. 

B. Slurry technique. A hot solution of 50% NaOH, 60 g, was dispersed in 300 ml of toluene and the slurry temperature was raised to 80 . After adding 36 g of cellulose and 0.018 mol of quat salt, the slurry was stirred at 110 for 1 hr. A quantitative transfer to a reactor provided an activated cellulose substrate for subsequent modification. 

TABLE 7. Poly(Butylacrylate) Via K2S20g/Quat Salts... 

Uses Chemical intermediate for prod, of quat. salts and amine oxides used in cosmetics catalyst for PU foam corrosion inhibitor Pmperties Hazen 50 cl. liq. sp.gr. 0.79 vise. 3.9 cps flash pt. 143 C (PMCC) 97% tert. amine... 

Figure 12.1 General mechanism of phase-transfer catalysis in the presence of quat salts ... 

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