Indene, chlorination

Cyclodienes. These are polychlorinated cycHc hydrocarbons with endomethylene-bridged stmctures, prepared by the Diels-Alder diene reaction. The development of these insecticides resulted from the discovery in 1945 of chlordane, the chlorinated adduct of hexachlorocyclopentadiene and cyclopentadiene (qv). The addition of two Cl atoms across the double bond of the ftve-membered ring forms the two isomers of chlordane [12789-03-6] or l,2,4,5,6,7,8,8-octachloro-2,3,3t ,4,7,7t -hexahydro-4,7-methano-lJT-indene, QL-trans (mp 106.5°C) and pt-tis (32) (mp 104.5°C). The p-isomerhas signiftcantiy greater insecticidal activity. Technical chlordane is an amber Hquid (bp 175°C/267 Pa, vp 1.3 mPa at 25°C) which is soluble in water to about 9 fig/L. It has rat LD qS of 335, 430 (oral) and 840, 690 (dermal) mg/kg. Technical chlordane contains about 60% of the isomers and 10—20% of heptachlor. It has been used extensively as a soil insecticide for termite control and as a household insecticide. 

AlClj Alkylation Process. The first step in the AIQ. process is the chlorination of / -paraffins to form primary monochloroparaffin. Then in the second step, the monochloroparaffin is alkylated with benzene in the presence of AIQ. catalyst (75,76). Considerable amounts of indane (2,3-dihydro-lH-indene [496-11-7]) and tetralin (1,2,3,4-tetrahydronaphthalene [119-64-2]) derivatives are formed as by-products because of the dichlorination of paraffins in the first step (77). Only a few industrial plants built during the early 1960s use this technology to produce LAB from linear paraffins. The C q—CC olefins also can be alkylated with benzene using this catalyst system. 

Butyl phenolic resin is a typical tackifier for solvent-borne polychloroprene adhesives. For these adhesives, rosin esters and coumarone-indene resins can also be used. For nitrile rubber adhesives, hydrogenated rosins and coumarone-indene resins can be used. For particular applications of both polychloroprene and nitrile rubber adhesives, chlorinated rubber can be added. Styrene-butadiene rubber adhesives use rosins, coumarone-indene, pinene-based resins and other aromatic resins. 

Tackifiers. Phenolic resins are added to increase strength, oils resistance and resiliency of NBR adhesives. On the other hand, tack and adhesive properties can be improved by adding chlorinated alkyl carbonates. To impart tack, hydrogenated rosin resins and coumarone-indene resins can be added. 

Nitrile rubber is compatible with phenol-formaldehyde resins, resorcinol-formaldehyde resins, vinyl chloride resins, alkyd resins, coumarone-indene resins, chlorinated rubber, epoxies and other resins, forming compositions which can be cured providing excellent adhesives of high strength, high oil resistance and high resilience. On the other hand, NBR adhesives are compatible with polar adherends such as fibres, textiles, paper and wood. Specific formulations of NBR adhesives can be found in [12]. 

Soufiaoui reported that arylnitrile oxides 10 can be generated under microwaves not only from aromatic oxime chlorides, such as 174, by the action of alumina (Method A) but also from aryloximes, such as 176, by the addition of a chlorination agent, N-chlorosuccinimide (NCS), supported on alumina (Method B) (Scheme 9.54) [29a]. Both methods afforded identical cydoadducts in similar yields - when indene was used as the dipolarophile the yield was 86%. In the absence of alumina, method B fails (reagents are less reactive and decompose) and method A does not yield any cydoadduct but a dimer of the dipole. 

Oxidation, of Grignard reagents with peresters, 41, 91 43, 55 of 2-hydroxy-3-methylbenzoic acid to 2-hydroxyisophthalic acid by lead dioxide, 40, 48 of indene, 41, 53 44, 63 of indolepyruvic add, 44, 66 of methyl disulfide to methanesul finy 1 chloride by chlorine, 40, 62 of 2-exo-norbomyl formate by chromic add, 42, 79... 

Chlordane is subject to hydrolysis via the nucleophilic substitution of chlorine by hydroxyl ions to yield 2,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methano-l//-indene which is resistant to hydrolysis (Kollig, 1993). The hydrolysis half-life at pH 7 and 25 °C was estimated to be >197,000 yr (Ellington et ah, 1988). 

Cabaleiro and Johnson (1967) report that the addition of chlorine to -methyl cinnamate in chloroform or acetic acid is syn-selective, SS 0-75, in chloroform and acetic acid acetoxychloro derivatives are produced as well. Again, Dewar and Fahey (1964) argue that the normal course of addition of hydrogen halides onto olefins is a polar electrophilic process involving classical carbonium ions as intermediates and leading mostly but not exclusively to cis-adducts. A syn-preference was found in the additions of deuterium bromide to acenaphthylene, indene, and cis- and fraws-phenylpropene. In the case of indene, phenylpropene and methyl cinnamate, which are styrene analogs, concerted syn addition is symmetry-allowed (see bottom of p. 273). 

The indene-derived group. At the Velsicol Chemical Corporation in Chicago in 19 3, Dr. Julius Hyman was seeking new uses for the cyclopentadiene which was a by-product of U.S. synthetic rubber production and was already used by Velsicol for the manufacture of resins and varnishes by the Diels-Alder reaction (6). A literature search revealed Straus s 1930 synthesis of hexachlorocyclopentadiene ( hex ) and, since chlorinated dienes are frequently rather inert, Hyman was interested to determine if hex would participate in the Diels-Alder reaction, either with itself or with cyclopentadiene. 

First, aluminum chloride abstracts the reactive benzylic fluorine from 1-phenylperfluoropropene and leaves a positively charged species that cyclizes to an indene derivative. The reactive benzylic fluorine atoms in this intermediate are replaced by chlorine [55] in a way similar to the replacement of fluorine by halogens in Explanations 22,23, and 24. 

Cationic polymerizations of styrene, 2-methylpropene, vinylnaphthalene, indene, etc. at temperatures about 273 K yield only low polymers. Polymerization of styrene with HC104 in chlorinated solvents at room tern-... 

Double dehydrobromination was also used in the preparation of 2-chloro-3a,7a-methanoindane (6). The dibromide, formed by brominating the corresponding monoalkene 5 at — 78 C, was treated with potassium ferr-butoxide in /ert-butyl alcohol, which gave 6 in 56% overall yield. Notably, this treatment left the chlorine atom intact. The chloride 6 served in turn as the starting material for the synthesis of 3a,7a-methano-l//-indene (see Section 5.2.2.1.1.3.)." ... 

Thermal dimerization of perchlorotolane cannot be carried out at moderate temperatures. At about 250°C, an excellent conversion to a mixture of the dimers perchloro-1,2,3-triphenylnaphthalene and perchloro-(Z)-2,3,8-triphenylbenzofulvene is obtained. Perchloro-5,10-diphenyldibenzo[a,e]-pentalene (perchloro-5,10-diphenylindeno[2,l-a]indene) is also formed this has been shown to originate from the fulvene by thermal chlorine-elimination (Ballester et al., 1986a). 

One of the chlorine atoms in phosphorus pentachloride appears to hold a unique position in that the products of the reaction mth indene, styrene, a-methylstyrene and 5 u.-diphenylethylene m cold benzene solution, suffer hydrolysis accompanied by intramolecular separation of the fifth chlorine atom as hydrogen chloride when treated with water. At much higher temperatures certain indones add on two chlorine atoms when treated with phosphorus pentachloride, this decisively indicating the fission PCI5 PClg + Clg. 

The stereochemistry of other photocycloadditions can be examined by considering, for instance, the reaction of cis and trans 1,2-dichloroethylene with indene , and the addition of dimethyl maleate and fumarate to acetone. In the former process (sensitised by benzophenone) two products syn and anti) are possible for each stereochemical relation of the two chlorine atoms. Taking together the two cis and the two trans products, the behaviour of the systems can be described as follows " ... 

Dichloroiodo)benzene can be convenientiy generated in situ from other hypervalent iodine reagents and used for subsequent chlorination of organic substrates. In a specific example, an efficient chlorination of p-keto esters, 1,3-diketones and alkenes has been performed using iodosylbenzene with concentrated HCl, selectively giving a-chloro-p-keto esters, 2-chloro-l,3-diketones and 1,2-dichloroalkanes, respectively [63]. A stereoselective anti-addition was observed in the chlorination of indene under these conditions. 

Uses Coumarene-indene in adhesives, aluminum paints, varnishes, rotogravure inks, rubber comf. food pkg. adhesives, rubber articles Features Exc. resist, to alkalis, dilute acids and moisture FtegMory FDA 21CFR 175.105,177.2600 Properties Gardner 11 (50% in toluene) solid sol. in esters, ethers, ketones (except acetone), chlorinated, aromatic, naphthenic, and terpene HC m.w. 525 sp.gr. 1.05 R B soften, pt. 45 C iodine no. (Wijs) 50 flash pt. (COC) 400 F Cumai R-27,10° [Neville]... 

In the attempt to unravel the biosynthetic origin of sporolides, and considering that these compounds are composed of a chlorinated cyclopenta[a]indene ring and a cyclohexenone moiety, it was hypothesized that the former fragment could be nonenzymatically derived from an unstable nine-membered enediyne precursor by the nucleophilic addition of chloride. Support to this suggestion came from sequence analysis of S. tropica CNB-440 genome, which led to the identification of two biosynthetic loci encoding enediyne PKSs. Analysis of the respective... 

Chlorinated paraffin (chlorocosane) n. Any of a family of yellow to light amber liquids produced by chlorinating a paraffin oil, with uses as secondary plasticizers for vinyls, polystyrene, polymethyl methacrylate, and coumarone-indene resins. Chlorinated paraffins also impart flame resistance to polyolefins, polystyrene, PVC, natural rubber, and unsaturated polyester resins. 

The efficiency of grafting indene from chlorinated butyl rubber was found to be enhanced by a side reaction in which indene homopolymer was grafted onto the macro-initiator. Efficiencies of 100% were obtained with this system. 

Chlorinated butyl rubber also contains a small amount of allylic chlorine. With diethyl aluminium chloride, cationic sites may be generated at these points on the chain leading to grafting in the presence of polymerizable monomers such as indene. ... 

The ruthenium-catalyzed [2+2+2] cycloaddition of a functionalized chloro-diyne with a functionalized propargylic alcohol furnished the corresponding chlorinated indene derivative as a single regioisomer. This product was successfully transformed into the natural product, sporolide B (Scheme 21.9) [12],... 

Miscellaneous Plasticizers. Hydrocarbons and halogenated hydrocarbons belong mainly to the secondary plasticizer type. Aromatic and aliphatic hydrocarbons are used as extenders coumarone-indene resins and coal tar oils are miscible with rubber and slightly miscible with vinyl polymers. Alkylnaphtha-lenes are used as lubricants for vinylic polymers. Chlorinated hydrocarbons are used as secondary plasticizers in PVC, rubber or cellulose acetate-based blends to increase the resistance to inflammation. 

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