Chlorobis

F.N. Tebbe (1978 [footnote 20]) and R.R. Schrock (1976) have shown that electrophilic titanium or tantalum ylides can alkylidenate the carbonyl group of esters. Vinyl ethers are obtained in high yields with Tebbe s reagent, p-chlorobis(ri -2,4-cyclopentadien-l-ylXdime-thylaluminum)- 4-methylenetitanium (S.H. Pine, 1980 A.G.M. Barrett, 1989). 

The stereospedfic and regioselective hydrobromination of alkynes with chlorobis(T -cyclopentadienyl)hydrozirconium and NBS produces ( )-vinylic bromides in good yields. The bromine atom usually adds regioselectively to the carbon atom that bears the smaller substituent and stereoselectively trans to the larger substituent (D.W. Hart, 1975 M. Nakatsuka,... 

A solution of potassium naphthalenide is prepared from 2.0 g (50 mmol) of potassium and 6.4 g (50 mmol) of naphthalene in 40 mL ofTHF. After 1 h at r.t. this mixture is diluted with 10 mL of diethyl ether and 10 mL of petroleum ether (bp 40-60 °C) and cooled to — 120 °C. 4.5 g (25 mmol) of ( )-l-methoxy-3-phenylthio-1-propcne arc added followed by 3.36 g (25 mmol) of chlorobis(l-dimethylamino)borane. This mixture is allowed to warm to r.t. over 3 h the solvents are removed in vacuo and the residue is carefully distilled through a 5-cm column at 10 2 Torr. The distillate, containing also naphthalene, is dissolved in 30 mL of diethyl ether and treated with 2.95 g (25 mmol) of pinacol for 3 h. The crude product is chromatographed over 30 g of basic alumina (activity 1) using petroleum ether (bp 40 -60°C) giving 9.2 g of a mixture of product and naphthalene the yield of product (89% E) is determined to be 60% by H-NMR analysis. Similarly prepared is ... 

Several trialkoxy(2-butenyl)zirconium(IV)6,7i 18 and 2-butenylbis(cyclopentadienyl)zirco-nium(IV)18,19 124 complexes have been investigated with respect to the diastereoselectivity on addition to aldehydes. Chlorobis(cyclopentadienyl)-(3-tributylstannyl-2-propenyl)zirconium(IV), prepared by hydrozirconation of tributyl-(l,2-propadienyl)tin, accomplishes the (E)-selective, Wittig-like 1,2-propenylidenation of aldehydes and methyl ketones125. 

Cobalt, cis-chloroamminebis(l, 2-ethanediamine)-optical isomerism, 1,12 Cobalt, chlorobis(l,2-ethanediamine)-solvation, 1,503... 

Blasco R, M Mallavarapu, R-M Wittich, KN Timmis, DH Pieper (1997) Evidence that formation of protoane-monin from metabolites of 4-chlorobiphenyl degradation negatively affects the survival of 4-chlorobi-phenyl-cometabolizing microorganisms. Appl Environ Microbiol 63 427-434. 

Baker, R.W. and Pauling, P. (1969) Molecular structure of chlorobis (pentafluorophenyl)triphenyl-phosphinegold(lll). Journal of the Chemical Society D Chemical Communications, (13), 745. 

Uson, R., Laguna, A. and Cuenca, T. (1980) Chlorobis (polyfluorophenyl) thallium(III) complexes and their reactions with gold(l) and tin(ll) compounds. Journal of OrganometaUic Chemistry, 194(3), 271-275. 

Uson, R., Laguna, A., Laguna, M., Uson, A. and Gimeno, M.C. (1988) Reactions of pentafluorophenyl(ylide)silver(I) or -gold (I) complexes with chlorobis... 

Baenziger, N.C., Dittemore, K.T. and Doyle, J.R. (1974) Crystal and molecular structure of chlorobis (triphenylphosphine) gold(l) hemibenzenate. Inorganic Chemistry, 13, 805-810. 

Trace elements in soils and sludges (CRMs 141R-146R 597) pp 225-232 (1998k) Chlorobi-phenyls in sewage sludge (CRM 392) pp 240-243 (1998I) Trimethyl-lead in urban dust (CRM 605) pp 274-278 In Production of Certified Reference Materials for Pollutants in Environmental Matrices. European Commission Report EUR 18157 EN, CCF Academic Press, Tarbes. 

See Dichlorodi-/r-chlorobis(pentamcthylcyclopentadienyl)dirhodium Air, Alkyl-metals... 

Schwartz s Reagent Bis(cyclopentadienyl)zirconium chloride hydride Zirconium, chlorodi-B-cyclopentadienylhydro- (8) Zirconium, chlorobis(ii5-2,4-cyclopentadien-1-yl)hydro- (9) (37342-97-5)... 

Chlorobis(ti5-cyclopentadienyl)hydridozirconium was prepared by lithium aluminum hydride reduction of the dichloro compound using the procedure of Buchwald and co-workers.4 When carried out using chlorobis(n5-cyclopentadienyl)-hydridozirconium obtained from a commercial source, the procedure afforded only a 28% yield of final product. 

The reaction of racemic Sb-chiral l-phenyl-2-trimethylsilylstibindole with the optically active ortho-palladated benzylamine derivative, di-p-chlorobis (S)-2-[l-dimethylamino)ethyl]phenyl-C,N dipalladium, leads to diastereomeric complexes which were used for the separation of the enantiomers of the stibindoles.65 The molecular structures of the diastereomeric palladium complexes are depicted in Fig. 4. 

Herrmann WA, Brossmer C, Reisinger CP, Riermaier T, Ofele K, Beller M (1997) Coordination chemistry and mechanisms of metal-catalyzed C-C coupling reactions. Part 10. Palladacycles efficient new catalysts for the Heck vinylation of aryl halides. Chem Eur J 3 1357-1364 Iyer S, Jayanthi A (2001) Acetylferrocenyloxime palladacycle-catalyzed Heck reactions. Tetrahedron Lett 42 7877-7878 Iyer S, Ramesh C (2000) Aryl-Pd covalently bonded palladacycles, novel amino and oxime catalysts di- x-chlorobis(benzaldehydeoxime-6-C,AT)dipalla-dium(II), di- x-chlorobis(dimethylbenzylamine-6-C,A)dipalladium(II) for the Heck reaction. Tetrahedron Lett 41 8981-8984 Jeffery T (1984) Palladium-catalysed vinylation of organic halides under solid-liquid phase transfer conditions. J Chem Soc Chem Commun 1287-1289 (b) idem,... 

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