Butyl acrylate Butyllithium

It is reported that methyl acrylate, allyl acetate, vinyl acetate and dimethyl maleate give only low yields of oligomers with butyllithium under all experimental conditions (31). Furukawa and coworkers (32) confirm that vinyl acetate will not polymerize and that n-butyl-vinyl-ether will not either. High polymers can be formed from isopropyl acrylate (39) in toluene at —70° and from t-butyl acrylate (65). The reported failure of methyl acrylate and butyl acrylate to yield high polymers could reflect a genuine difference in behaviour connected with the side group or. could simply result from failure to choose the most favourable conditions for polymerization. Vinyl acetate can be polymerized by lithium metal (49) but co-polymerization experiments suggest that the polymer is formed by a radical mechanism. 

Sodium dispersions in hexane yield syndiotactic poly(methyl methacrylate). A 60-65% conversion is obtained over a 24-hour period at a reaction temperature of 20-25 C. Lithium dispersions, butyllithium, and Grignard reagents " "yield crystalline isotactic poly(r-butyl acrylate). The reactions take place in bulk and in hydrocarbon solvents. Isotactic poly(isopropyl acrylate) forms with Grignard reagents. ... 

Diphenylmethylcarbanions. The carbanions based on diphenyl-methane (pZ a = 32) (see Table 1) are useful initiators for vinyl and heterocyclic monomers, especially alkyl methacrylates at low temperatures (46). 1,1-Diphenylalkyllithiums can also efficiently initiate the polymerization of styrene and diene monomers that form less stable carbanions. Diphenylmethyl-lithium can be prepared by the metalation reaction of diphenylmethane with butyllithium or by the addition of butyffithium to 1,1-diphenylethylene, as shown in equation 17. This reaction can also be utihzed to prepare ftinctionalized initiators by reacting butyffithium with a substituted 1,1-diphenylethylene derivative. Addition of lithium salts such as hthium chloride, lithium f-butoxide, or lithium 2-(2-methoxyethoxy)ethoxide with 1,1-diphenylmethylcarbanions and other organolithium initiators has been shown to narrow the molecular weight distribution and to improve the stabffity of active centers for anionic polymerization of both alkyl methacrylates and t-butyl acrylate (47,48). 

The adducts of either butyllithium with DPE (1,1-diphenylhexyllithium) or polymeric organolithiums with DPE are the preferred initiators for polymerization of a wide variety of alkyl methacrylates and (ert-butyl acrylate [3]. For example, Stiihn and coworkers [77] recently reported the synthesis of well-defined, narrow molecular weight distribution polymers from methyl, ethyl, n-propyl, -butyl, n-pentyl, and n-hexyl methacrylates using the adduct of scc-butyllithium and DPE as initiator in THF at -78 °C in the presence of lithium chloride. This initiator was also used recently to copolymerize 2-tri-methylsiloxyethyl methacrylate and butyl methacrylate using analogous reaction procedures [78]. 

Some information is available on other acrylates. N,N-disubstituted acrylamides form isotactic polymers with lithium alkyls in hydrocarbons (12). t-Butylacrylate forms crystallizable polymers with lithium-based catalysts in non-polar solvents (65) whereas the methyl, n-butyl, sec-butyl and isobutyl esters do not. Isopropylacrylate also gives isotactic polymer with lithium compounds in non-polar solvents (34). The inability of n-alkylacrylates to form crystallizable polymers may result from a requirement for a branched alkyl group for stereospecific polymerization. On the other hand lack of crystallizability cannot be taken as definite evidence of a lack of stereoregulating influence, as sometimes quite highly regular polymer fails to crystallize. The butyllithium-initiated polymers of methylmethacrylate for instance cannot be crystallized. The presence of a small amount of more random structure appears to inhibit the crystallization process1. 

Conjugate Additions. The reaction of this acrylate derivative with lithium t-butyl hydroperoxide (generated from anhydrous t-Butyl Hydroperoxide and n-Butyllithium) in THF leads to the corresponding epoxide (eq 5) in 95% yield with a de of 40%. ... 

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