Vinyltin compounds

Arylation and Alkylation of Alkenes by Vinyltin Compounds The Stale Reaction... 

Arylation and alkylation of alkenes by vinyltin compounds (the Stille... 

It is commonly known that vinyltin compounds undergo no free-radical polymerization and do not readily copolymerize with various vinyl monomers which can be attributed to their inhibiting effect towards radical reactions48,79. ... 

Vinyltin compounds are very important in organic synthesis, since the vinyl moiety can be readily transferred to carbon in the (palladium-catalyzed) Stille reaction. The transfer is stereospecific, and the geometry of the vinyltin moiety can be easily checked using proton and carbon-13 NMR via the coupling satellites. 

By regiospecific [4+2] cycloadditions of functional alkenyltin derivatives with dienes such as 1,3-butadiene, 2,3-dimethyl-l,3-butadiene or 1-substituted 1,3-butadienes, polyfunctional cyclic vinyltin compounds 80 are obtained. 

The fluorodestannylation with XeF2 takes place rapidly at room temperature in the presence of 2,6-di-t-butyl-4-methylpyridine, fast enough for introducing the short-lived 1SF isotope, and is thought to involve the initial formation of triflic hypofluoride, F3CSO3F, and then its adduct with the vinyltin compound (Equations (74)-(76)).228... 

Table 9. Fluorination of Vinyltin Compounds with F-Teda BF4 (6) in Acetonitrile88...

This general procedure has been used to prepare x3 a large number of vinyltin compounds, including ... 

The stabilizing effect of organotin compounds can also be used for internal stabilization. In this respect, a French patent of 1957 suggests copolymerization of vinyl chloride with small amounts of a vinyltin compound (e.g., the vinyldiethyl laurate of tin), which considerably improves the thermal stability over homopolymeric vinyl chloride (8). An American patent of 1959 suggests two types of organotin compounds as stabilizers (13) ... 

Treatment of vinyllin compounds with xenon difluoride in dichloromethane at 25"C results in low yields of the desired vinyl fluorides with the major products being the corresponding alkenes. In addition to the poor yield of the desired compound the reaction times are long (2-3 d). Attempts to increase the reactivity of the vinyltin compounds by the addition of... 

One of the most convenient synthetic routes for the preparation of vinyl fluorides 2 is by treatment of the corresponding vinyltin compounds 1 with electrophilic fluorinating reagents. This procedure is also used for the preparation of aryl fluorides, since it is well-established that fluorination with electrophilic reagents is facilitated by ipso substitution of a suitable, usually weakly bonded, metal function. In the case of aryl fluorides, the reaction is also carried out using elemental fluorine as the fluorinating agent. ... 

Xenon difluoride (XeF ) is the electrophilic fluorinating reagent whose reactions with vinyltin compounds have been studied most exhaustively. " A series of vinyl fluorides prepared according to this procedure is listed in Table 1. 

Table 1. Synthesis of Vinyl Fluorides by Reaction of Vinyltin Compounds with Xenon Difluoride...

Vinyl fluorides are obtained regioselectively (Table 1, entries 2 and 3) and stereospecifically (Table 1. entries 10 and 11). The vinyltin compounds in Table 1, entries 9 and ll are 1 1 mixtures of ZjE isomers the same ratio is observed in the final vinyl fluorides. 

Fluorination of Vinyltin Compounds with Cesium Fluoroxysulfate Geueral Procedure ... 

CSSO4.F (1.3 mmol) was added portionwise to an ice-cooled solution of the vinyltin compound (1 mmol) in CHjClj/MeOH (1 1. 20 mL) under Nj and stirred for 2 h at 0 C (ice bath), then at rl overnight. The mixture was diluted with CH Clj, filtered and the filtrate purified by flash chromatography. 

Xenon difluoride is a better fluorinaling reagent for vinyltin compounds than cesium fluoroxysulfate (compare entry 1 in Tables 1 and 2). Besides this, cesium fluoroxysulfate (which can be prepared from elemental fluorine and cesium sulfate) is known to be shock sensitive and to undergo detonation upon hcaling. However, cesium fluoroxysulfate is the alternative choiee in the ease of some vinyltin compounds, such as 2- and 3-(trimethylstannyl)indolcs (Table 2, entries 5 7), whose reactions with xenon difluoride are not effective. 

Terminal difluoro- and fluoroalkenes 7 can be prepared in good yields by reaction of the corresponding fiuorovinyltin or vinyltin compounds with 1 -(chloromethyl)-4-fluoro-1,4-diazonia-bicyclo[2.2.2]octane bis(tetrafluoroborate) (Table 3)."... 

Table 3. Synthesis of Terminal Fluoroalkenes by Reaction of Vinyltin Compounds with F-Teda BF ...

Fluorination of Vinyltin Compounds with t-(Chloromethyl)-4-fluoro-l,4 iazoniabicyclo 2.2.2]octane Bis(tct-rafluoroborate) (F-Teda BFj ) General Procedure ... 

Vinyltin compounds can be generated from the corresponding vinyl-Grignard reagents or vinyllithium compoimds with a... 

S.8.5.6.2. by Reaction of Vinyltin Compounds with Transition- or Inner Transition-Metal-Carbonyl Complexes. 

Vinyltin compounds can react with metal carbonyls with either loss or retention of vinyl groups. The extent of reaction depends upon the solvent e.g., (CH2=CH)4Sn reacts with Co2(CO)g in THF to give (CH2=CH)Sn[Co(CO)4]3, whereas in pentane it gives (CH2=CH)2Sn[Co(CO)4]2... 

---