Stibines tertiary

As shown in the following reaction scheme, tertiary stibines R(C6H5)2Sb and [ (C6H5) 2Sb]2 (CH2) were obtained in good yields by a cleavage re- 

7 Recently, Meinema el al. (86) reported that an alkyl-antimony bond of R3Sb (R = alkyl) is also cleaved by sodium in liquid ammonia. 

It was also found that the phenyl-antimony bonds of (CH3) (C6H5)2Sb were cleaved selectively by dry hydrogen chloride in chloroform to give CH3SbCl2 (40). This cleavage reaction was successfully applied to the preparation of new ligands,11 bis(diorganostibino) methanes (41), as follows  

Properties of Asymmetrical Tertiary Stibines and Resolution of Quaternary Stibonium Iodide 

As shown in Table III, the PMR spectra of phenylmethylbenzylstibine and phenylmethylisopropylstibine in CDC13 at 23° show an AB quartet 

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Another exceUent method for preparing tertiary stibines involves the interaction of an organostibide and an alkyl or aryl haHde (91,92). This method is of particular value in preparing un symmetrical tertiary stibines. For example, an interesting hybrid ligand has been obtained by the foUowing reaction carried out in Hquid ammonia (93) ... 

Tertiary stibines have been widely employed as ligands in a variety of transition metal complexes (99), and they appear to have numerous uses in synthetic organic chemistry (66), eg, for the olefination of carbonyl compounds (100). They have also been used for the formation of semiconductors by the metal—organic chemical vapor deposition process (101), as catalysts or cocatalysts for a number of polymerization reactions (102), as ingredients of light-sensitive substances (103), and for many other industrial purposes. 

Tertiary stibines, R3Sb, are the most frequently used antimony ligands and the coordination chemistry of these donors to transition metals of the groups 3-12 and also to main group 13 and 15 elements has been reviewed several times, often together with other pnicogen ligands.1,2,6-8... 

From a structural point of view the complexes with tertiary stibine ligands are very uniform. The predominant type is rj coordination (type 1), with electron pair donation of the Sb atom to the metal centre.1,2,6,8 However, complexes with bridging stibine ligands (type 2) are also known.13,14 (Scheme 1). 

Recently, also the coordination of a tertiary stibine to antimony acceptors with formation of a coordinative Sb-Sb bond was investigated. Examples are the complexes of Me3Sb with SbMeI2,47 Sbl348 or Me2Sb +. 49... 

Related to tertiary stibines is the (Me3Si)3Sb ligand. Recent studies of this ligand comprise coordination on transition metal and main group element centers. An example for a transition metal complex with a known crystal structure is [(CO)5CrSb(SiMe3)3],5° the structure of which is depicted in Fig. 2. 

A novel type of ligands are tertiary stibines containing heterocyclic aromatic groups (Y-2-C4H3)3Sb (Y = S, O, or NMe) which with silver nitrate form polymeric 2 1 complexes, [ (Y-2-C4H3)3Sb 2AgN03]x.56... 

Bridging coordination of a tertiary stibine ligand (type 2) occurs in binuclear complexes of rhodium (Equation 1).13,14... 

When a RSb moiety is coordinated to two or three 17-e- complex fragments the resulting compounds compare well with tertiary stibines,... 

There is an extensive chemistry of tertiary phosphine rhodium(III) complexes. However, there are comparatively few complexes of monodentate tertiary arsines, although the complexes of ditertiary arsines are more numerous. There are virtually no tertiary stibine complexes. The two main preparative routes to the complexes described in this section are (i) direct reaction pf the ligands with rhodium trichloride, which usually yields trichloro complexes and (ii) oxidative addition to rhodium(I) tertiary phosphine complexes, which gives rise to more diverse products of the type [RhXYZ(PRj) ], Metathetical reactions on the complexes prepared by either method (i) or (ii) have been used to prepare most of the remaining compounds. 

One interesting reaction undergone by the tri(styryl)arsine complexes is the bromination of the C=C bond by bromine in CC14 (equation 217).1013 Similar behavior970 is exhibited by the few tertiary stibine complexes (Table 75) that have been isolated. Few physical properties of these complexes have been investigated, but the 121 Sb Mossbauer parameters for both rhodium(III) complexes and the free ligands have been determined.1016... 

A common method for the synthesis of tertiary stibines with alkyl, aryl, or other organic groups is the reaction between Grignard reagents and SbCls (equation 1) in diethylether or tetrahydrofiiran. 

Other useful organometallic reagents for the preparation of tertiary stibines or related heterocyclic compounds are compounds of lithium, aluminum, tin, copper, zirconium, and other metals. " In most cases, these metal compounds are reacted with antimony chlorides or bromides. Good yields of tertiary stibines were, however, also obtained by the interaction (equation 3) of triaUcylaluminium reagents and tris(dimethylamino)stibine. ... 

Tertiary stibines are volatile liqnids or solids. The aryl derivatives are air-stable bnt the trialkyl stibines are air-sensitive compounds, with at least the lower members being spontaneously flammable in air. They are strong redncing agents and can be used for the removal of halogen atoms from many substrates. 

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