60973-59-3Relevant articles and documents
A crystallographic and spectroscopic study on the reactions of WCl 6 with carbonyl compounds
Dolci, Sara,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
, p. 5635 - 5648 (2013/06/05)
WCl6, 1, reacted with two equivalents of HC(O)NR2 (R = Me, Et) in CH2Cl2 to afford the W(vi) oxo-derivatives WOCl4(OCHNR2) (R = Me, 2a; R = Et, 2b) as main products. The hexachlorotungstate(v) salts [{OC-N(Me)CH2CH2CH 2}2(μ-H)][WCl6], 3, and [PhNHC(Me)N(Ph)C(O) Me][WCl6], 4, were isolated in moderate yields from the 1:2 molar reactions of 1 with N-methyl-2-pyrrolidone (in CH2Cl2) and acetanilide (in CDCl3), respectively. The additions of two equivalents of ketones/aldehydes to 1/CH2Cl2 yielded the complexes WOCl4[OC(R)(R′)] (R = Me, R′ = Ph, 5a; R = R′ = Ph, 5b; R = R′ = Me, 5c; R = R′ = Et, 5d; R = H, R′ = 2-Me-C6H4, 5e) and equimolar amounts of C(R)(R′)Cl2. Analogously, WOCl3[κ2- {1,2-C6H4(O)(CHO)}], 5f, and 1,2-C6H 4(OH)(CHCl2) were obtained from 1 and salicylaldehyde. The 1:1 reaction of 1 with acetone in CH2Cl2 resulted in the clean formation of WOCl4 and 2,2-dichloropropane. Compounds 5a,b,f were isolated as crystalline solids, whereas 5c,d,e could be detected by solution NMR only. The interaction of 1/CH2Cl2 with isatin, in a 1:1 molar ratio, revealed to be a new, convenient route for the synthesis of 3,3-dichloro-2,3-dihydro-1H-indol-2-one, 6. The 1:1 reactions of 1 with R′OCH(R)CO2Me (R = H, R′ = Me; R = Me, R′ = H) in a chlorinated solvent afforded the tungsten(v) adducts WCl 4[κ2-OCH(R)CO2Me] (R = H, 7a; R = Me, 7b). 1/CH2Cl2 reacted sluggishly with equimolar quantities of trans-(CO2Et)CHCH(CO2Et) and CH2(CO 2Me)2 to give, respectively, the W(iv) derivatives WCl4[κ2-CH2(CO2Me) 2], 8a, and [WCl4-κ2-{trans-(CO 2Et)CHCH (CO2Et)}]n, 8b, in about 70% yields. The molecular structures of 2a, 3, 4, 5a, 5f, 7a and 7b were ascertained by X-ray diffraction studies.
Nitrile ylide dimerization: Investigation of the carbene reactivity of nitrile ylides
Fergus, Suzanne,Eustace, Stephen J.,Hegarty, Anthony F.
, p. 4663 - 4669 (2007/10/03)
A series of novel hexaaryl diazatrienes 5 ("nitrile ylide dimers") were synthesized directly from the corresponding diaryl ketimines 12 and dichlorotoluenes 13 in a facile one-pot synthesis. The carbene character of the nitrile ylides was investigated by varying the substituents on the aromatic ring adjacent to the carbene center. The isolation of the corresponding carbene dimers as stable crystalline materials with absorption maxima (λmax) from 363 to 422 nm was shown to be promoted by the absence of strongly electron-withdrawing substituents. The crystal structures indicate that the E-isomers were isolated when phenyl, 3-methylphenyl, and 3-chlorophenyl substituents are present at the carbene carbon; the Z-isomer was isolated when the more sterically hindered 2,4,6-trimethylphenyl substituent (Mes) is present. The 1H NMR spectra of the E-isomers demonstrate the nonequivalence of the aromatic rings, in which two of the aromatic rings of the imine moiety are pseudoaxial and the remaining aromatic rings are pseudoequatorial. The reactions proceed via the intermediate nitrile ylides 1 generated by the base-promoted 1,1-elimination of HCl from the intermediate chloroimine 14. The nitrile ylide was also generated by 1,3-elimination of HCl from the imidoyl chloride 18, confirming common pathways via the nitrile ylide as the dimer products obtained from these different routes were identical. The strongly electron-withdrawing 4-nitrophenyl substituent promotes the linear carbanion character of the 1,3-dipole and no dimer is formed.
A simple and efficient procedure for the preparation of benzal chlorides and benzal bromides
Léonel, Eric,Paugam, Jean-Paul,Heintz, Monique,Nédélec, Jean-Yves
, p. 4015 - 4024 (2007/10/03)
Benzal chlorides and benzal bromides were conveniently synthesized by reaction of aryl aldehydes with a Vilsmeier type reagent formed in situ by reduction of CCl4 or CBr4 in dimethylformamide (DMF) as solvent.
