Allyl alcohols chlorination

From Allyl Alcohol. The reaction of allyl alcohol [107-18-6] with chlorine and water gives a mixture of glycerol m on ochl orohydrin s consisting of 73% 3-chloropropane-l,2-diol and 27% of 2-chloropropane-l,3-diol (57). In a recycle reaction system in which allyl alcohol is fed as a 4.5—5.5 wt % solution, chlorine is added at a rate of 7—9 moles per hour. The reaction time is about five seconds, the reaction temperature 50—60°C and the recycle ratio is 10—20 1. Under these conditions m on ochl orohydrin s have been obtained in 88% yield with 9% dichlorohydrins (58) (see Allyl ALCOHOL AND DERIVATIVES). 

From Allyl Alcohol. An alternative route to dichlorohydrias from aHyl chloride begias with the hydrolysis to aHyl alcohol. Significant yields of 2,3-dichloropropanol can be obtained from the reaction of chlorine with allyl alcohol if the reaction is performed ia the presence of concentrated hydrochloric acid (65). Several patents for the manufacture of 2,3-dichloropropanol by the chlorination of allyl alcohol at low temperature, —30° to +20° C, ia 25—40% HCl solution have appeared (66—68). Product yields as high as 98% are claimed. 

CH2 CH.CH2.OH mw 58.09 OB to C02 -220.35% colorl, mobile liq with a pungent odor mp —129° bp 96.9°, d 0.8520g/cc at 20/4° RI 1.4127, 1.4133, 1.4135 (Sep values). V sol in w, ethanol and ether. Prepn is by the high temp chlorination of propene, followed by hydrolysis of allyl chloride. Thus,. . Allyl chloride is hydrolyzed at 200psi pressure, 150°C and a pH range of 10—12. Injection of steam forms a water-allyl alcohol azeotrope, which is then treated with diallyl ether to remove water. Final purification by distn leads to a 98% min assay. . (Ref 2). Using procedures such as the above, ... at least two American companies (Shell Chemical Co and Dow Chemical Co) produce a total of several million lbs per year... (Ref 2)... 

An interesting way to control the stereoselectivity of metathesis-reactions is by intramolecular H-bonding between the chlorine ligands at the Ru-centre and an OH-moiety in the substrate [167]. With this concept and enantiomerically enriched allylic alcohols as substrates, the use of an achiral Ru-NHC complex can result in high diastereoselectivities like in the ROCM of 111-112 (Scheme 3.18). If non-H-bonding substrates are used, the selectivity not only decreases but proceeds in the opposite sense (product 113 and 114). 

The reaction of HOC1 with allenes also yielded a mixture of regioisomeric allylic alcohols with the chlorine atom connected to the central carbon atom and the OH connected to the more substituted carbon atom [15]. 

With the aid of density functional theory, the ZnCl2 acceleration of the Simmons-Smith reaction of ethylene and allyl alcohol has been investigated. A pathway involving direct Lewis acid acceleration of the leaving halogen atom (327) was found to be a more facile process than the more popular pathway involving 1,2-chlorine migration (328). 

In an alternate synthesis, the allyl chloride is hydrolyzed with NaOH to produce allyl alcohol (H2C = CH-CH2-OH). This is then chlorinated to give monochlorohydrin and dichlorohy-drin, which are hydrolyzed with sodium bicarbonate to produce glycerol. 

Allyl Chloride. The manufacture of allyl chloride, commercialized in 1945, was the first of several modem high-temperature chlorination technologies applied for hydrocarbons. Preheated dry propylene mixed with dry chlorine in a ratio of 4 1 is reacted at 500-510°C to produce allyl chloride.193-195 Chlorine reacts quantitatively in a few seconds. The main byproducts are isomeric monochloropropenes and dichloropropenes. Allyl chloride is used mainly in the manufacture of allyl alcohol and glycerol via epichlorohydrin. 

Displacement of the chlorine atom in 203 with sodium allyloxide in allyl alcohol gave 7-allyloxy-l,2,4-triazolo[l,5-a]pyrimidine (204). This was followed by a thermal Claisen rearrangement to 205-209 in addition to 152. Allylation of 152 with allyl bromide gave the two allylated products 206 and 207 (63CPB851) (Scheme 38). 

This derivative, abbreviated AC, is a transparent, mobile, and irritative liquid. It can be easily synthesized from allyl alcohol and hydrogen chloride. However, it is industrially produced by chlorination of propylene at high temperature,... 

ALLYL CHLORIDE. See Chlorinated Organics Allyl Alcohol and Monoallyl Derivatives. 

Allyl Chloride (3-chioropropene-1). [CAS 107-05-1]. Ally I chloride can be synthesized by reaction of allyl alcohol with HCI or by treatment of allyl formate with HCI in the presence of a catalyst (ZnCLV Commercial production is by chlorination of propylene at high temperatures, about 500°C. using a large excess of propylene. It is used in the synthesis of... 

The epoxy alcohol 47 is a squalene oxide analog that has been used to examine substrate specificity in enzymatic cyclizations by baker s yeast [85], The epoxy alcohol 48 provided an optically active intermediate used in the synthesis of 3,6-epoxyauraptene and marmine [86], and epoxy alcohol 49 served as an intermediate in the synthesis of the antibiotic virantmycin [87], In the synthesis of the three stilbene oxides 50, 51, and 52, the presence of an o-chloro group in the 2-phenyl ring resulted in a lower enantiomeric purity (70% ee) when compared with the analogs without this chlorine substituent [88a]. The very efficient (80% yield, 96% ee) formation of 52a by asymmetric epoxidation of the allylic alcohol precursor offers a synthetic entry to optically active 11 -deoxyanthracyclinones [88b], whereas epoxy alcohol 52b is one of several examples of asymmetric epoxidation used in the synthesis of brevitoxin precursors [88c]. Diastereomeric epoxy alcohols 54 and 55 are obtained in combined 90% yield (>95% ee each) from epoxidation of the racemic alcohol 53 [89], Diastereomeric epoxy alcohols, 57 and 58, also are obtained with high enantiomeric purity in the epoxidation of 56 [44]. The epoxy alcohol obtained from substrate 59 undergoes further intramolecular cyclization with stereospecific formation of the cyclic ether 60 [90]. 

The /rans-3 -benzylth io-3-ch Ioro- ( -1 actams 192, the appropriate (3-lactam car-bocation equivalents, were prepared by stereospecific chlorination of their corresponding frans-3-benzylthio-(3-lactams 191 using IV-chlorosuccinimide and catalytical amount of AIBN [125]. These (3-lactam carbocation equivalents 192 on treatment with propargyl alcohol or allyl alcohol in the presence of ZnCVSiCL were further transformed to suitable substrates, such as, m-3-benzylthio-3-(prop-2-ynyloxy/enyloxy)-(3-lactams 193 and 195 respectively [126]. 

The two chlorinated propene compounds shown are colorless liquids with pungent, irritating odors. Allyl chloride is an intermediate in the manufacture of allyl alcohol and other allyl compounds, including pharmaceuticals, insecticides, and thermosetting varnish and plastic resins. Dichloropropene compounds have been used as soil fumigants, as well as solvents for oil, fat, dry cleaning, and metal degreasing. 

An alternative route involving acetoxylation of butadiene and has come on stream, and, more recently, a route based upon hydroformylation of allyl alcohol has also been used. Another process, involving chlorination of butadiene, hydrolysis of the dichlorobutene, and hydrogenation of the resulting butenediol, has been practiced. 

An unprecedented one-pot stereoselective synthesis of 2-azetidinone P-chlorinated allylic alcohols 23, which can also be considered as functionalized allylsilanes, has been developed, by tin(IV) chloride-mediated reaction of propargyltrimethylsilane and 4-oxoazetidine-2-carbaldehydes <02CEJ1719>. An explanation for the formation of P-chlorovinyl alcohols involves a stepwise process with the chlorination proceeding via a silicon stabilized carbocation. 

The organozinc intermediate thus formed reacts with aldehydes as Grig-nard reagents do to form alcohols. In the presence of aluminum chloride, elimination of chlorine and fluorine from the vicinal carbons of the dichlorotrifluoroethyl group generates halogenated allylic alkoxides that are protonated to allylic alcohols, in the present case J, 2-chloro-3,3-difluoro-1 -phenylpropen-2-ol [114]. 

The first thing that happens is that the lone pair on phosphorus attacks one of the chlorine atoms in the chloroketone. The leaving group in this S 2 reaction at chlorine is an enolate, which is a basic species and can remove the proton from the OH group in the allylic alcohol. 

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