1 : 2-Dichloro-l -propene

Oda et al. reported that under reflux conditions, the zinc-promoted reaction of 2,3-dichloro-l-propene with aldehydes and ketones in a two-phase system of water and toluene containing a small amount of acetic acid gave 2-chloroallylation products (Eq. 8.31).64 No conversion occurred when tin was used as the promoter. The absence of water completely shuts down the reaction. Interestingly, the action of 2,3-dichloropropene plus zinc powder in aqueous ethanol gives the dechlorination product, allene.65... 

Bieber reported that the reaction of bromoacetates is greatly enhanced by catalytic amounts of benzoyl peroxide or peracids and gives satisfactory yields with aromatic aldehydes. A radical chain mechanism, initiated by electron abstraction from the organometallic Reformatsky reagent, is proposed (Scheme 8.27).233 However, an alternative process of reacting aldehydes with 2,3-dichloro-l-propene and indium in water followed by ozonolysis provided the Reformatsky product in practical yields.234 An electrochemical Reformatsky reaction in an aqueous medium and in the absence of metal mediator has also been reported.235... 

Chlorination of simple allenes in CH2C12 with or without BF3 afforded a mixture of 2,3-dichloro-l-propene and propargyl chloride [11, 12]. 

Neudecker, T. Henschler, D. (1986) Mutagenicity of chloroolefms in the Salmonellalvaaawaa.-lian microsome test. III. Metabolic activation of the allylic chloropropenes allyl chloride, 1,3-dichloropropene, 2,3-dichloro-l-propene, 1,2,3-trichloropropene, l,l,2,3-tetrachloro-2-pro-pene and hexachloropropene by S9 mix via two different metabolic pathways. Mutat. Res., 170, 1-9... 

DICHLORO-l-PROPENE see DGH400 DICHLOROPROPENE (DOT) see DGG950 (Z)-l,3-DICHLOROPROPENE see DGH200 cis-l,3-DICHLOROPROPENE see DGH200... 

An alternative procedure for the synthesis of 1-propynylphosphonic ester uses the Michaelis-Arbuzov reaction of 2,3-dichloro-l-propene with triisopropyl phosphite to produce almost quantitatively diisopropyl 2-chloroallylphosphonate. On treatment with aqueous methanoUc NagCOj solution at room temperature, it is converted into diisopropyl 1-propynylphosphonate by a dehydrochlorination-isomerization sequence (Scheme 4.25). ... 

DICHLOROPROPENE or 2,3-DICHLORO-l-PROPENE (78-88-6) Forms explosive mixture with air (flash point 122°F/50°C). Reacts violently with strong oxidizers. Incompatible with strong acids, oxidizers, active metals, aluminum or magnesium compounds, aliphatic amines, alkanolamines, alkaline materials. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

BUTYROLACTONES 2,3-Dichloro-l-propene. Dichlorotrisftriphenylphos-phine)ruthenium(ll). Lithioallyltri-methylsilane. Lithio -lithiopropio-nate. 

CjHjCy 1,2-Dichloroallyl Cl 1 Photolysis of DTBP in 2,3-dichloro-1-propene/ 2,3-Dichloro-l-propene DTBP EPR/ 198 H(l,3,3) 1.35 (5) 73Ricl... 

The dehydrochlorlnatlon of 1,2,3-trlchloropropane, which was obtained by the distillation of Shell s still bottoms, with 30% aqueous sodium hydroxide afforded 2,3-dichloro-l-propene in 88% yield (27). 

The addition of chlorine to 2,3-dichloro-l-propene furnished 1,2,2,3-tetrachloropropane (28-29) in 90% yield which when reacted with a base afforded a 32% yield of trans 1,2,3-trichloropropene, bp 75 °C (100 mm) and a 26% yield of the cis isomer, bp 87 C (100 mm) (29). Hatch et al., (29) were the first to separate and identify these isomers. 

Utilization of the procedure reported by Wheeler and Bares (50-55), 2-chloroallyl dimethyIthiolcarbamate, an active herbicide, was obtained in fair yield by heating a mixture containing ethyl dimethyl-thionocarbamate and 2,3-dichloro-l-propene at 110-115 °C (39). 

The following mechanism is proposed for reaction 20 which involves the 1,2-addition of 2,3-dichloro-l-propene to thiocarbonyl moiety followed by the elimination of ethyl chloride. (Scheme 1.)... 

N-Allenylpyrroles (Table 2.14) have been synthesized by the reaction of pyrroles with 2,3-dichloro-l-propene (readily obtainable from 1,2,3-trichloropropane, side product in the epichlorohydrin manufacture) in the KOH/DMSO suspension (KOH is used in fourfold molar excess relative to 2,3-dichloro-l-propene) (Scheme 2.124) [591,595]. 

SCHEME 2.124 Synthesis of N-allenylpyrroles from pyrroles and 2,3-dichloro-l-propene in KOH/DMSO system. 

SCHEME 2.125 Expected steps of the pyrroles allenylation by 2,3-dichloro-l-propene. 

Dehydrochlorination of 2,3-dichloro-l-propene to propargyl chloride, which reacts with pyrroles as described previously, is not also excluded. Obviously, these two directions can occur in parallel. 

Tarasova, O.A., A.I. Mikhaleva, T.L. Markova, and B.A. Trofimov. 1992. N-AUenylation of pyrroles with 2,3-dichloro-l-propene. Khim Geterocicl 1 125. 

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