Pseudo-halogens

Few of the many other inorganic compounds of Ge, Sn and Pb call for special comment. Many pseudo-halogen derivatives of Sn, Pb and Pb have been reported, e.g. cyanides, azides, isocyanates, isothiocyanates, isoselenocyanates and alkoxides. ... 

The disulfide is dissolved by aqueous potassium hydroxide, yielding a greenish-yellow solution. At low temperatures no perceptible evolution of gas takes place. Since the disulfide in many respects behaves as a pseudo-halogen, Brown et al. have supposed that the reaction described by Eq. (8) takes place, i.e. a reaction analogous to the formation of halide and halite ions from a halogen and alkali. 

Copper-catalyzed ATRP is a multicomponent system, consisting of a monomer, an initiator with a transferable (pseudo)halogen, and a copper complex (composed of a copper (pseudo)halide and nitrogen-based complexing ligand). For a successful... 

Scheme 4.14 Pathway for the selective hydrogenation of polyenes to monoenes catalyzed by PtX2(QPh3)2/SnCI2 Q= P or As, X=halogen or pseudo-halogen.

Alkynenitriles can be obtained from metallated acetylenes and the "pseudo-halogen DON [114,115] ... 

The synthesis of organozinc compounds by electrochemical processes from either low reactive halogenated substrates (alkyl chlorides) or pseudo-halogenated substrates (phenol derivatives, mesylates, triflates etc.) remains an important challenge. Indeed, as mentioned above, the use of electrolytic zinc prepared from the reduction of a metal halide or from zinc(II) ions does not appear to be a convenient method. However, recent work reported by Tokuda and coworkers would suggest that the electroreduction of a zinc(II) species in the presence of naphthalene leads to the formation of a very active zinc capable of reacting even with low reactive substrates (equation 23)11. 

Homoleptic complexes with bidentate C C donor ylide derivatives are well known. Oxidative addition of some gold(I) [Au2 (CH2)2PR2 2] species by addition of halogen, pseudo-halogen, or alkyl halide affords dinuclear Au(II) complexes which... 

Pseudo-halogens may be used in a similar manner. The pseudo-interhalogens C1N3 or BrN3 react with iron pentacarbonyl to produce a remarkable bridged, binuclear, doubly charged cation, which is paramagnetic. 

The influence of other phenyl substituents on anti-proliferative effects has also been studied. In one study, a series of halogen or pseudo-halogen para-substituted compounds with X = Cl, (Z)-21 Br, (Z)-22 CF3, (E)-23 and CN, ( )-24 and... 

MacDiarmid, A. G. Pseudo-Halogen Derivatives of Monosilane. J. Inorg. and Nucl. Chem. 2, 88 (1956). 

The hydrolysis of thiocyanogen (SCN)2 in warm base yields sulfate, cyanide, and thiocyanate ions. Show how this hydrolysis is in conformity with the picture of the —SGN as a pseudo-halogen group. (Hint recall the hydrolysis of the halogens under similar conditions.)... 

Reactions with R2S2 and S8- In their reaction with l, di-methyl and diphenyl disulfide behave as pseudo-halogens giving the bridged complexes, 20 (eq. 45). These complexes are also obtained from the reaction of R2S2 with Cp2Mo2(C0)6 under more forcing conditions (56,6). 

The reaction of sodium atoms with allyl alcohol is also somewhat unusual since the e.s.r. spectrum of the deposit showed that trapped electrons were not present and that the allyl radical was formed exclusively even at 77°K. Thus if electrons were trapped initially the trap must have decomposed rapidly to form the allyl radical and a hydroxyl ion. Such a reaction might occur in this case because of the much weaker CO-bond in the allyl alcohol. Alternatively the alkali metal atom might have reacted directly with the alcohol, the hydroxyl group behaving like a pseudo-halogen group. 

A stabilization of the chalcogen(II) dihalides is possible by complex-ation with various electron pair donors (see Section III,D). A stabilization of the simple molecular species is also obtained if the halogens are substituted by pseudo-halogens. This situation is similar to the anionic halo- and pseudo-haloselenates(II) (Section III,B). As examples, Se(CN)2, Se(SCN)2, and Se(SeCN)2 could be prepared in crystalline form (182, 273). In Se(SCN)2 and Se(SeCN)2 the molecules are linked via secondary Se-"N bonds to form chains, with a distorted square planar coordination of 2 S(Se) and 2 N around the central Se (182). 

It is known that the p-tolylsulfonyloxy group has the properties of a pseudo-halogen and that treatment of a p-toluenesulfonate by the salt of an acid can produce the replacement of the p-tolylsulfonyl group by the acyl group, through a Sn2 reaction (for references, see Ref. 39). 

N-Chloro-N-cyclohexylbenzenesulfonamide, CsHsSC NClCfiH,. [1, 130, before Chlorodiazomethane]. Mol. wt. 273.78, m.p. 89°. This pseudo halogen is obtained as an oil which slowly crystallizes after digestion with petroleum ether. 

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