Aryltins

With tetiaaiyltin compounds, the reaction can proceed further to the aryltin trihalides ... 

By reaction with the appropropriate aryl halides can be prepared a variety of aryltin compounds that are not accessible from the reactions involving arylmagnesium halides and organotin halides (88,89) there is evidence that an aryne intermediate may be involved (90). However, for some purposes, such as the addition to carbonyl compounds, ox-iranes, and oxetanes, to give hydroxyalkyltin compounds, the Sn-Mg reagents may have advantages (see Section II,E) (91-93). 

These reactions to form aryl tin bonds could occur by initial oxidative addition of the aryl halide or the distannane. The stoichiometric reaction between [(PPh3)2Pd(Ph)(I)] and Me3SnSnMe3 in the presence of chloride generated good yields of the aryltin product. This result suggests that the reactions occur by initial oxidative addition of aryl halide. 

Diaryl- or dialkylmercury compounds can be used for the synthesis of mixed aryltin chlorides326, or for alkylation of SnF2338 or SnX4339 (Scheme 26). Functional halostan-nanes can be prepared by a variety of methods. 

The ortho-arylation of 2-arylpyridines with aryltin reagents is mediated by Wilkinson s catalyst. This cross-coupling procedure occurs at high temperatures and consequently, the prevention of double phenylation represents a major hurdle, which is often achieved by adding a methyl group to either the pyridine or aryl group (Equations (125) and (126)).1... 

Aryloxytitanium halides, 25 83 2-Arylpyridines, 27 111 Aryl phosphate esters, 79 51 Aryl phosphates, 7 7 493 Aryl phosphonates, 79 37 Arylphosphorus compounds, 79 28 Aryls, palladium, 79 652 Aryl-silicon compounds, 22 553, 554 Arylsulfinic acids, 27 248-249 Arylsulfonylated gelatin, 72 444 Aryltin trihalides, 24 810-811 Arylyl amines, 70 396-399 Asahi Chemical Industries EHD processes, 9 676-677 sebacic acid production, 9 679-680 ASAM (alkaline-sulfite-AQ-methanol) process, 27 30... 

The two most important reactions of aryltin compounds are first, their reaction with electrophiles, when either the tin or the non-tin product may be the aim, or, second, the coupling reactions that they show in the presence of certain transition metals (Equation (51)). 

Reduction of the aryltin(ll) chlorides with lithium, sodium, or potassium for some days gives the dianions, with the alkali metals sandwiched between aryl rings from different terphenyl groups. 

River sediment Alkyltin, aryltin Benzene extraction conversion to hydride with NaBH4, glc with electron capture detector 0.02 [77] 0.0001 -0.08 (coastal and marine)... 

The Sonogashira coupling of halopyridines was also achieved by other means. Resin bound bromopyridine derivatives, for example, underwent smooth coupling with acetylenes as well as with arylboronic acids and aryltin reagents.44 The advantageous effect of microwave irradiation on the coupling of halopyridines and trimethylsilylacetylene was also reported.45... 

Unactivated aryl iodides undergo the conversion Arl — ArCHj when treated with tris(diethylamino)sulfonium difluorotrimethylsilicate and a palladium catalyst.131 A number of methods, all catalyzed by palladium complexes, have been used to prepare unsymmetrical biaryls (see also 3-16). In these methods, aryl bromides or iodides are coupled with aryl Grignard reagents,152 with arylboronic acids ArB(OH)2,153 with aryltin compounds Ar-SnR3,154 and with arylmercury compounds.155 Unsymmetrical binaphthyls were synthesized by photochemically stimulated reaction of naphthyl iodides with naphthoxide ions in an SrnI reaction.156 Grignard reagents also couple with aryl halides without a palladium catalyst, by the benzyne mechanism.157 OS VI, 916 65, 108 66, 67. 

Aryltin and arylmercury derivatives are converted into fluorobenzene (34) with yields being higher in the case of mercury derivatives.53 56... 

The palladium-catalyzed reaction of aryl- and vinyl-tin reagents with stereochemically defined allyl chlorides proceeds with overall retention of configuration, indicating that the second step, entailing interaction of the iT-allylpalladium complex and the organotin, proceeds by transmetallation and reductive elimination (attack at Pd, retention) (equations 166 and 167).142145 Comparable results were obtained with cyclic vinyl epoxides and aryltins.143... 

The impurities such as grease, acids, or metals act as catalysts and the driving force of the overall reaction of Eq. (133), once it is initiated, is the formation of a gaseous and solid phase. With careful exclusion of such catalysts, alkyl or aryltin hydrides appear to be stable indefinitely at room temperature. 

Ohe, T. Uemura, S. A novel catalytic activity of Bi(III) salts in Pd(II)-catalyzed atom economical Michael-type hydroarylation of nitroalkenes with aryltin compounds. Tetrahedron Lett. 2002, 43, 1269-1271. 

Various alkyl and aryltin compounds were determined in aquatic matrices, namely sediments, biota and water by means of gas chromatographic methods. In this work, comparisons of single or dual flame photometric detectors and electron capture detectors were reported (Tolosa et al., 1991). Sample preparations included acid digestion, extraction, formation of methyl derivatives and clean-up with alumina prior to gas chromatographic analysis. With the electron capture detector, cold on-column injection of organo-tin chlorides was studied. The conclusion was that a single or dual flame photometric detector equipped with a 600 nm interference filter yielded the best performance for determinations of tin species as methyl derivatives. Detection limits for the method using flame... 

Phenylpyridine is arylated by using aryltin reagents such as Ph4Sn in the presence of a rhodium catalyst (Eq. 15) [21]. The use of a halogenated solvent is important for obtaining a satisfactory yield. Although the precise mechanism is not yet clear, it is likely that a cyclometalated intermediate participates. 

Additional examples of the application of mass spectrometry have been described for less common compounds such as furyl and thienyl germanes86, germatranes87, acetylene derivatives of Ge88 and alkyl and aryltin oxinates89,90. 

The reduction of bivalent aryltin chloride by sodium anthracenide in THF gave a new way to a bulky distannylanion in the form of a stable very close ion-pair (equation 54)71. The X-ray crystal structure reveals a normal Sn-Sn distance (2.81 A) in the distannylanion and a Sn—Na bond length of 3.24 A. 

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