Cyclooctadiene chloride

At the end of the process the hydrogenation product was hydrolyzed with HBr (Fig. 13) and benzoic acid was recycled. The rhodium was recycled by adsorption on a cation exchanger KP2 from Wolfen (sulfonated polystyrene crosslinked by 2% divinylbenzene) [35], 80% of the rhodium could be removed, the residual rhodium accumulated in the final mother liquor which contained only a very small amount of L-dopa. This mother liquor and the loaded ion exchanger were ashed and the resulting rhodium reacted with chlorine under heating to redness to give rhodium(III)-chloride. This was used directly for the synthesis of the dimer rho-dium(I)-cyclooctadiene-chloride from which rhodium(I)-cyclooctadiene-acetylaceto-nate could easily be obtained. 

Fig. 5. Structiires of iridium(cyclooctadiene)chloride dimer and its oxidation product.

Photolytic reactions of dienes frequently give complex mixtures of rearranged products. Described here, however, is a photolytic isomerization of 1,5-cyclooctadiene (present in solution, in part, as a complex with cuprous chloride) that affords a good yield of one product. 

There is an absence of cis-to-trans isomerization with conversion or time for the C8 (1,5-cyclooctadiene) polymer. This is shown from 52 to 58% conversion after 1 to 16 hours reaction time in Table II and III. The above review (A0, A2, A3, A5) shows that the cis structure in polymers from 1,5-cyclooctadiene using various chloride catalysts fell below 50% cis even to 20% cis units this means that the second cis double bond from the monomer underwent extensive cis-to-trans isomerization following the ring-opening of the first cis bond. Where cis-2-butene isomerizes to trans structure using other catalyst preparations, there is no evidence of this for cis-2-butene using the iodine system. However, polymer molecular... 

In contrast to Ni, alkylpalladium precursors can be easily prepared and isolated owing to their greater stability (Scheme 2). The monomethyl chloride adducts of formula (diimine)PdMeCl can be conveniently synthesized via diimine displacement of other weakly coordinating ligands, such as COD from Pd(COD)MeCl (COD = 1,5-cyclooctadiene) [44], or by in situ alkylation-complexation with tetramethyltin [52], The chloride ligand can then be cleanly abstracted by metathesis with NaBAF... 

The same stereochemical behavior has also been observed in the addition of ben-zeneselenenyl chloride to 1,5-cyclooctadiene (3) (equation 136). However, 3 reacts with... 

Kahn and Chen (87TL1623) performed the regio- and stereospecific reaction of 1,3-cyclooctadiene and acyliminium derivative 79, which resulted exclusively in compounds 80 in 37% yield after chromatographic purification. 79 was prepared by treatment of the A-methylimine of benzal-dehyde with methyl chloroformate in the presence of titanium(IV) chloride. 

An N-heterocyclic carbene ligand, formed from l,3-bis-(2,4,6-trimethylphenyl)-3//-imidazol-l-ium chloride and cesium carbonate, with dipalladium tris(dibenzylideneacetone) gave excellent yields (93-96% yields) in the Suzuki coupling of 2-chloropurines and arylboronic acids in anhydrous dioxane <2001TL8751>. The combination of an imidazolium-carbene and nickel(O) bis(cyclooctadiene) formed a catalyst capable of insertion into the C-F bond of 6-fluoropurine nucleosides (Scheme 35) <20050L1149>. 

Die radikalische Aminierung von 1,5-Cyclooctadien mittels Hydroxylamin/Titan(III)-chlorid in konzentrierter Salzsaure verlauft unter gleichzeitiger transannularer Addition und ergibt exo-2-Amino-cis-bicyclo[3.3.0]octan2. Die Stoffbilanz dieser Reaktion entspricht einer einfachen Addition von Ammoniak an das Dien. 

ALCOHOLS Allyltrimethylsilane. (1,5-Cyclooctadiene)bis(methyldiphenylphos-phine)iridium hexafluorophosphate. Guaiacylmcthyl chloride. Lcvulinic acid. (3-( Primethylsilyljethoxymethyl chloride. 2-(Trimethylsilyl)ethyl chloroformate. Trimelhyllrityloxysilane. 

Method C. 100 mg (0.4 mmol) of bis[/z-chloro l,2,5,6-> 4-cyclooctadiene (l,5) rhodium], [RhCl(>74-C8H12)]23, is dissolved in 10 mL of methylene chloride and 0.68 g (1.2 mmol) of tppts in 10 mL of water is added. The two-phase system is stirred intensively for 30 min. Then the reaction mixture is transferred to a separation funnel. The aqueous phase is separated and the organic phase extracted twice, in each case with 5 mL of water. The combined aqueous phases are then washed twice with methylene chloride (2x5 mL). The water solution is transferred into a round-bottomed flask and the solvent is removed in a vacuum (10 2 torr). The raw product obtained is sufficiently pure for most reactions. Depending on the stoichiometry, small amounts of tppts or (>74-C8H12)Rh2(/r-Cl)2(tppts)2 are present, which can be removed by column chromatography on Sephadex G-15. Yield 740 mg (93%) red glass-like solid. 

Nonconjugated dienes and polyenes have triplet photochemistry which may be considered to arise from intramolecular interaction of one excited double bond with an isolated ground-state double bond. For example, the photocyclization of enrfo-dicyclopentadiene can be effected using acetone as a sensitizer.286 Other more flexible 1,5-dienes, when sensitized to triplet states, cross couple to yield bicyclo[2.1.1]-hexane structures. For instance, triplet mercury atoms convert both 1,5-hexadiene and 1,5-cyclooctadiene to such structures.267 Irradiation of the cyclooctadiene in the presence of cuprous chloride produces the tricyclo derivative in good yield266 but recent evidence again indicates that this latter reaction may proceed via free-radical intermediates.269... 

Asymmetric hydrovinylation.1 The reaction of ethylene with 1,3-cyclohex-adiene catalyzed by bis(l,5-cyclooctadiene)nickel, diethylaluminum chloride, and 1 gives ( + )-(S)-3-vinyl-l-cyclohexene (2) in quantitative yield and 93% ee. Related ligands prepared from (S)-proline and D-ephedrine are less effective for asymmetric hydrovinylation. 

N-Benzyl-N-methoxymethyl-N-(tri-methylsilyl)methylamine, 31 Bis( 1,5-cyclooctadiene)nickel(0), 35 Lithium diisopropylamide, 163 N-Methyl-N, O-bis(trimethylsilyl) -hydroxylamine, 187 Titanium(IV) chloride-N-Methylani-line, 310... 

Bis(l, 5-cyclooctadiene)nickel(0), 35 t-Butyllithium, 58 Diacetatobis(triphenylphosphine)-palladium(II), 91 Menthol, 172 Mercury(II) chloride, 175 Palladium(II) acetate, 232 2-(Phenylseleno)acrylonitrile, 244 Potassium t-butoxide, 252 Tributyltin hydride, 316 Triphenyltin hydride, 335... 

Bis[2,2 -bis(diphenylphosphine)-l,l -binaphthyl] (tetrachloro) (triethyl-amine) diruthenium, 36 Bis( 1,5-cyclooctadiene)nickel(0)-Di-ethylaluminum chloride-Threophos, 298... 

Allyldiisobutylaluminum, 302 Alumina, 14, 174, 217, 254, 256 Aluminum chloride, 15, 46, 174 Aluminum iodide, 17 Aluminum isopropoxide, 265, 352 Bis(l,5-cyclooctadiene)nickel(0)-Diethylaluminum chloride-Threo-phos, 298... 

Dimethylthexylsilyl trifluoromethane-sulfonate, 74 Diphenylsilane, 153 Diphenylsilane-Di- x-chlorobis(l,5-cyclooctadiene)dirhodium, 153 Diphenylsilane-Palladium(II) chloride-Triphenylphosphine, 126 Diphenylsilane-Tetrakis(triphenyl-phosphine)palladium(0)-Zinc chloride, 126... 

Thiiranes can be formed directly and stereospecifically from 1,2-disubstituted alkenes by addition of trimethylsilylsulfenyl bromide, formed at -78 C from reaction of bromine with bis(trimethylsilyl) sulfide (Scheme 7).12 A two-step synthesis of thiiranes can be achieved by addition of succinimide-A/-sulfe-nyl chloride or phthalimide-A -sulfenyl chloride to alkenes followed by lithium aluminum hydride cleavage of the adducts (Scheme 8).13 Thiaheterocycles can also be formed by intramolecular electrophilic addition of sulfenyl chlorides to alkenes, e.g. as seen in Schemes 914 and 10.13 Related examples involving sulfur dichloride are shown in Schemes 1116 and 12.17 In the former case addition of sulfur dichloride to 1,5-cyclooctadiene affords a bicyclic dichloro sulfide via regio- and stereo-specific intramolecular addition of an intermediate sulfenyl chloride. Removal of chlorine by lithium aluminum hydride reduction affords 9-thiabicyclo[3.3.1]nonane, which can be further transformed into bicyclo[3.3.0]oct-1,5-ene.16... 

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