3- Chloro-2-chloromethyl-l-propene

The next four procedures describe the preparation of strained ring systems. Preparation of 3-CHLORO-2-(CHLOROMETHYL)-l-PROPENE provides a facile approach to the olefin required for the synthesis of [1.1.1 [PROPELLANE, one of the most strained hydrocarbons prepared to date. The ready availability of this hydrocarbon should prove particularly useful to those interested in the development of the chemistry of this fascinating compound. Preparation of N-BENZYL-2,3-AZETIDINEDIONE provides an efficient approach to the unadorned a-keto-/3-lactam, a potential... 

Chloro-2-(chloromethyl)-l-propene is commercially available but is very expensive (> 45/g for 10 g, Aldrich Chemical Company, 1996). It is commonly used in the synthesis of natural products,5 polymers,6 cryptands and crown ethers,7 compounds of biological and medical importance,8 and is the starting material for the Szeimies synthesis of [1.1.1]propellane.9... 

Preparation of (R)-l involves the chlorination of (R)-l,l-bina-phthyl-2,2-dicarboxylic acid with scc-BuLi and hexachloro-ethane. Condensation of the resulting dichorinated product with 3-chloro-2-chloromethyl-l-propene, followed by oxidative cleavage of the olefin moiety with ruthenium trichlorde affords (R)-l in modest yields. 

Bis(alkene) derivatives of crown thioethers may also be prepared [2-1-2] reaction of 1,4,7-trithiaheptane with 3-chloro-2-chloromethyl-l-propene in the presence of B(OPr)3/Al(OPr), gave 9,19-dimethylene-20S6 in 67% yield <93AG(E)436>. 

Related Reagents. Methallyl chloride Methallyl Bromide Methallyl Alcohol 3-Chloro-2-chloromethyl-l-propene 2-Methylene-1,3-propanediol. 

Polyethylene Glycol-Based Membranes Brylev et al. [149] synthesized new AEMs based on polyethylene glycol (PEG). They prepared amorphous anionconducting polyether networks by cross-linking a quaternary ammonium salt with an unsaturated prepolymer (Rg. 5.16). The synthesis took place in two steps. The first step was a polycondensation between PEG and 3-chloro-2-chloromethyl-l-propene. Second, simultaneous cross-linking and functionalization took place. The chloride conductivity of these polymers was on the order of 1 X 10 S/cm at 25 C and no result in terms of hydroxyl conductivity was given. 

Allyl chloride, " propenyl chloride isomers, trichloroethylene,l,3-dichloro-2-butene, 3-chloro-2-chloromethyl-1-propene, and chloroprene are all claimed to undergo alternating copolymerization with MA. Isopropenyl chloride is essentially nonpolymeriz-able by both free-radical and ionic initiators. However, mixtures of isopropenyl chloride and MA in benzene with AIBN, at 60°C, copolymerize quite readily to give colorless materials, with relatively high viscosities. The composition of the copolymers were found to be independent of monomer feed ratio and to consist essentially of a 1 1 composition of the monomer pair. In contrast, cis- and -propenyl chloride exhibit low copolymerization rates with MA and the resultant copolymers exhibit much lower specific viscosities than the isopropenyl chloride-co-MA polymers. 

A. 1,1-Dibromo-2,2-bis(chloromethyl)cyclopropane (1). Into a 1-L, threenecked, round-bottomed flask, equipped with an efficient mechanical stirrer, a thermometer, and a condenser equipped with a potassium hydroxide drying tube, are placed 54.1 g (0.403 mol) of 3-chloro-2-(chloromethyl)propene (Note 1), 212 g (0.805 mol) of bromoform (Note 2), 1.70-2.00 g (14.4-16.9 mmol) of pinacol (Note 3), and 1.45 g (3.94 mmol) of dibenzo-18-crown-6 (Note 4). With very vigorous stirring (Note 5), 312 g of an aqueous 50% sodium hydroxide solution that has been cooled to 15°C is added in one portion. The reaction mixture turns orange, then brown, then black within 5 min, and the temperature of the reaction mixture begins to rise. Within 20 min, the internal reaction temperature is 49-50°C at which point the reaction flask is cooled with a room-temperature water bath, and the reaction temperature decreases to ca. 

Zirconacyclopentadienes 23 (R = R = R = R = Et, Pr", Bu", M = Zr, Cp =Cp) react with l,4-dibromo-2-butyne in the presence of CuCl via a tandem inter-intra-molecular cyclization to yield 2,3,4,5-tetrasubstituted styrenes (Equation 11) <2002T1107>. 3-Chloro-(2-chloromethyl)propene reacts with the same set of zirconacyclopentadienes in the presence of CuCl to yield tetrasubstituted methylene cycloheptadienes. Reaction with 3,4-dichlorobutene under identical conditions yields vinylcyclohexadienes. In both cases, tandem inter-intra-molecular allylation occurs. 

Chlorination of liquid methylenecyclopropane with gaseous chlorine at 0°C yielded a mixture of 3-chloro-2-(chloromethyl)propene (2, 73%) and l-chloro-l-(chloromethyl)cyclopropane (1, 21%) An electrophilic attack of a chlorocation was assumed as 2,4-dichlorobut-l-ene, one of the major products of the photochlorination of methylenecyclopropane, was not formed. ... 

In addition to high yields, this procedure can be used in the presence of functional groups such as C=0 or C=C [131]. Thus 3-thia-l,5-pentanedithiol reacts with 1,3-dichloroacetone and 3-chloro-2-(chloromethyl)propene in the presence of a 5 1 (j-PrO)3B/(/-PrO)3Al couple afifording mainly 2-f2 macrocyclic products LI394 and L1395 in 42% and 67% yield (Eq. 6.40) [131] only small amounts of 1 -f-1 species could be identified. The X-ray crystal structure of L1394 is available [131J. 

Alternatively, 2-(chloromethyl)-3-iodo-l-propene reacted with aldehydes or ketones to give after basic treatment methylenetetrahydrofuran in excellent yields. The reaction is as expected chemo- and regioselective conjugated carbonyl compounds gave 1,2-addition, and aldehydes react more preferably than ketones [106]. Simharly, 3-chloro-homoallylic alcohols were prepared in high yields from the reaction of 2,3-dichloropropene with carbonyl compounds in a two-phase system containing a small amount of acetic acid. In this reaction, the presence of water in the reaction medium was shown to be essential as the reaction did not occur under non-aqueous conditions [107]. 

---