Triorganotin hydrides reactions

With the simple triorganotin hydrides, reaction 15-31 occurs only in the presence of a Lewis base such as an amine, or of a transition metal catalyst. The amine-catalysed reaction has been used for preparing catenary and cyclic oligostannanes (e.g. equations 15-33 and 15-34 and Section 18.2.1.3).92... 

The reaction between triorganotin hydrides and organic halides is known since 1957 68). Analogous reactions have been described for chiral triorganosilicon69) and -germanium 70) hydrides, which are stereoselective. It is well known that they proceed via the triorganometal radical, which can also be formed photochemically from metallated ketones 71). 

Triorganotin hydrides do react with HMn(CO)5 to give Mn2(CO)10 and the expected (triorganostannyl)pentacarbonyl manganese80. In THF, only these two compounds are formed. In benzene, in addition to these two products, the hexa-organoditin and some starting product are found in the reaction mixture. 

The first optically active organotin, where the metal atom is the only chiral center, was synthesized132 using tetra-p-anisyltin as starting material. A racemic triorganotin hydride was first prepared by the sequence of reactions... 

In the case of triorganotin hydrides, the reaction with R3SnX (where X = OAc, Cl, I, CN) requires the presence of triethylamine as a catalyst99. 

Reactions of triorganotin hydrides with amines resulted in the formation of the corresponding ditin species according to equation 4454- 56. 

Triorganotin hydrides are common reductants in a large number of organic and organo-metallic syntheses. In many cases these reductions proceed by a normal radical reaction pathway. However, ionic reductions using tin hydrides also occur, but they were only sparsely investigated. Studies of ionic reduction processes with tin hydrides by using Sn NMR are found elsewhere . 

Organotin hydrides can undergo either heterolytic or homolytic reactions. Reactions with carboxylic acids and with R)SnX (X = OR, NR2, or other nucleophilic groups) are considered to be heterolytic reactions. Other heterolytic reactions of triorganotin hydrides are shown in Scheme 12. 

Various tin-tin bonded compounds are known. The simplest tin tin bonded compounds, hexaorganoditins, RsSnSnRs, are available by several routes, including (i) from triorganotin halides and alkali metals in ether or liquid ammonia (equation 65) (ii) from triorganotin hahdes and triorganotin lithium compounds (equation 66) and (iii) from triorganotin hydrides in the presence of a base (such as pyridine) or on reaction with Sn-O, Sn-N, or Sn-S species (Scheme 14). 

II Reaction of organotin amides with triorganotin hydrides ... 

Allylstaimanes are available from reactions of allybnagne-sium or allyllithium compounds with tin halides (equation 32). Other syntheses involve reactions of triorganotin anionic species with allylic halides or esters (equation 14), as well as reactions of allylic xanthates, tosylates, etc. with tin hydrides (equation 33). 

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