Telomer chlorides

The first three telomers CCl2Br(CH2CHCl)nBr (n = 1 - 3) were isolated as individual compounds, the structure was confirmed by NMR spectroscopic data. The values of the chain transfer partial constants (Cj = 7 C2 = 54.3) point to the high efficiency of CBr2Cl2 as a chain transfer agent, which comparable with that of CBr4 (C2 = 74.2) (in the similar reaction with vinyl chloride) (ref. 7). 

Several additives were tested in the case of the Ni(acac)2/P(n-Bu)3/AlEt3/addihve (1/3/3/10) system. BF3.0Et2 or TiCl4 or morpholinium chloride induces the fully se-lechve formahon of 3-(N-morpholino)-l-butene without formahon of 1 2 telomers or oligomers (Eq. 4.46) [180]. 

Hydrosilanes react with butadiene by the catalysis of palladium compounds, but the nature of the reaction is somewhat different from that of the telomerization of other nucleophiles described before. Different products are obtained depending on both the structure of silanes and the reaction conditions. Trimethylsilane and other trialkylsilanes reacted with butadiene to give the 1 2 adduct, l-trialkylsilyl-2,6-octadienes (65), in high yield (98%) (62-64). Unlike other telomers which have the 1,6-octadienyl chain, the telomers of silanes have the 2,6-octadienyl chain. As catalysts, Pd(PPh3)2 (maleic anhydride), PdCl2(PhCN)2, PdCl2, and 7r-allylpalladium chloride were used. Methyldiethoxysilane behaved similarly to give the 1 2 adduct. 

Decenoic acid (143), easily prepared from the same telomer 142, was cyclized via acid chloride using A1C13 to give 2-pentyl-2-cyclopentenone (144). Michael addition of methyl malonate followed by removal of one ester group produced methyl dihydrojasmonate (145) (129) ... 

To further exploit the potential usefiilness of this new family of clusters, monoadduct 54 was saponified into 55 (0.05 M NaOH, quant) and condensed to L-lysine methyl ester using 2-ethoxy-l-ethoxycarbonyl-l,2-dihydroquinoline (EEDQ) to give extended dimer 56 in 50 % yield together with monoadduct in 15 % yield [75]. Additionally, tert-butyl thioethers 52 could be transformed into thiols by a two step process involving 2-nitrobenzenesulfenyl chloride (2-N02-PhSCl, HOAc, r.t, 3h, 84%) followed by disulfide reduction with 2-mercaptoethanol (60%). Curiously, attempts to directly obtain these thiolated telomers by reaction with thioacetic acid f ed. These telomers were slightly better ligands then lactose in inhibition of binding of peanut lectin to a polymeric lactoside [76]. 

Cobalt(III) fluoride can be used116 to remove traces of hydrocarbon from a vinyl chloride/ sulfuryl chloride telomer, and to saturate117 the double bonds in a poly(cyclobutene) to form... 

The catalyst system with the 1,3-dimesitylimidazolium chloride ligand (IMes) that worked exceptionally well for ethylene glycol [78] also worked well for the conversion of 1,3-propanediol, 1,3- and 1,4-butanediol and 1,4-pentanediol. Chemoselectivities for the mono-telomer are in the range of 74-94%. Somewhat surprisingly, the conversion found for 1,3-propanediol was lower than for either ethylene glycol or 1,4-butanediol. 

Vinyl chloride was telomerized both with 2-hydroxyethyl trichloroacetate and 2,4,4,4-tetrachlorobutanoI (the latter compound is the monoadduct of allyl alcohol and CCI4) using redox initiation lll). Telomers bearing at chain end a hydroxy group were obtained ... 

Vinylidene chloride was previously investigated in the living redox telomer-ization using CC14 as the transfer agent, as follows [108, 145] ... 

Telomerizatum of monochlorotrifluoroethykne. Carbon tetrachloride, in combination with ferric chloride, triethylamine hydrochloride, and benzoin (as reducing agent), and with acetonitrile as solvent, reacts with monochlorotrifluoroethylene to give telomers of the formula (1). 

Another original macromonomer, based on VAc, afforded interesting properties however the functionalization of such a monomer remains difficult [252,268-270]. The group of Sato [269,271-275] suggested the synthesis of VAc macromonomer by functionalization onto VAc telomers, obtained with 2-mercaptoethanol. The functionalization can be realized with acryloyl chloride, giving macromonomers with different molar masses (Table 24). 

In a similar way, Wood and Cooper [268] used isopropoxyethanol as a transfer agent and the telomers were then functionalized with methacry-loyl chloride however, only 28% of the telomers were functionalized with methacryloyl chloride. Macromonomers were then copolymerized with styrene in dispersion copolymerization, in the presence of 1,1,2,2-tetrafluoroethylene. Such copolymers have been used as dispersing agents for the styrene polymerization in supercritical CO2. 

Other workers have reported the preparation of methyl methacrylate-styrene and methyl methacrylate-vinyl chloride block copolymers by a two stage free radical polymerization. First they prepared telomers of styrene (or vinyl chloride) and poly(methyl methacrylate) terminated by carbon tetrachloride. Then they heated the telomers of the desired monomers in the presence of bis-(ephedrine) copper to prepare sequential ABAB block copolymers(87). Poly(methyl methacrylate-b-acrylonitrile) was prepared by heating (CO)5Mn(CF2)2 terminated poly(methyl methacrylate) and acrylonitrile at 100 C(88) ... 

Product mixtures from radical chain addition of hydrogen chloride to olefins are much more complicated than is the case for hydrogen bromide. The problem is that the rate of abstraction of hydrogen from HCl is not large relative to addition of the alkyl radical to the olefin, and this results in the formation of short polymers called telomers ... 

Telomerization of 1,4-butadiene with water, alcohols, amines, and acids is an extremely useful reaction since it leads to the formation of practically important products. (179,180). For example, the telomer with water, 2,7-octadiene-l-ol can be further hydrogenated to 1-octanol which is a raw material for plasticizers for poly(vinyl chloride). In fact, this reaction was among the processes disclosed in the first patents on the use of TPPTS in biphasic solvent mixtures (58). The catalyst for such telomerizations usually consists of palladium(O) and an excess of TPPTS, TPPMS, or other water-soluble phosphines (eg, with quaternary ammonium substituents). The telomerization of 1,4-butadiene with water was developed into an industrial process by Kuraray Ind. (Scheme 26). Interestingly, the best ligand was the phosphonium salt shown in (Scheme 26) and the catalyst could be prepared in situ from this ligand and [Pd(OAc)2] (179). It is assumed that under the reaction conditions the corresponding tertiary phosphine can be formed to some extent and coordinates to palladium. In any case with a large excess of... 

Preparation and applications of vinyl chloride-carbon tetrachloride telomers [257, 258]. 

Also, other ten-membered lactones can be conveniently prepared starting from the primary acetates, as outlined in Equation 6. Again the terminal double bond of the telomer is oxidized in a Wacker—Hoechst-type reaction yielding a methyl ketone. After conversion into an allylic chloride and treatment with phenylthioacetylchloride an intramolecular alkylation yields the lactone-ring [8]. 

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