Organotin amines

The condensation used recently for the synthesis of alkynyltins from monosubstituted acetylenes with organotin amines, oxides, and halides 135, 160, 193, 253) has been shown by Davies and Puddephatt to be successful with organolead compounds 45). 

Sllmicide, Organotin Amine Blend 125 F. Slimicids, Polychlorophenate-... 

N-Ethylaminotrimethylsilane allowed to react with Irimethyltin bromide, and the resulting complex heated with distillation of the product -> N-ethylamino-trimethyltin. Y 72%.—Tert. organotin amines had to be prepared by another method because of the increased thermal stability of the intermediate complex. E. W. Abel, D. Brady, and B. R. Lerwill, Chem. Ind. 1962, 1333 (ferf-amino)-stannanes from aminomagnesium halides cf. K. Sisido and S. Kozima, J. Org. Chem. 27, 4051 (1962). 

The first representative of this class, tetrakis(diethylamino)tin, Sn[N-(C2Hs)2]4, was described in 1961 (52). The reagent used in its preparation, LiN(C2H5)2, afterwards proved to be equally suited to the preparation of other organotin amine derivatives. 

In 1962 the field of organotin amine chemistry was at last opened up with the publication of four papers (53, 54, 55, 56) on the preparation of compounds of general formula i Sn(NR R")4 covering all possibilities from = 0 to n = 3. In one of these papers (56), moreover, compounds with more than one tin atom joined to the same nitrogen atom, as well as a cyclic compound of the formula [R2SnNR ]3, were described. 

Early in the same year the synthesis of compounds in which a triorganotin group is bound to heterocyclic nitrogen was announced (42). In contrast to the organotin amine derivatives, these are very stable to moisture provided a second nitrogen occurs at the 3-position with respect to the first in the heterocyclic ring. It was shown that this is due to a stabilization of tjie crystalline state through pentacoordination around the tin atom. 

The organotin amine compounds, with a few exceptions, are liquids. They are extremely sensitive toward moisture when exposed to the air they immediately liberate amine or ammonia. Thermal stability on the other hand is good. Most compounds can be distilled without decomposition. From NMR studies it has been concluded 86) that the tin-nitrogen bond in diethylaminotin compounds is purely covalent. 

Organotin Amines, Phosphines, Arsines, Stibines and Bismuthines... 

Fio. 5. Some reactions of the tin-nitrogen bond in organotin amines. 

Some syntheses of the organotin amines are outlined in equation form below, and some of the extensive reactions o of this class are illustrated in Fig. 5. It is obvious from Fig. 5 that the organotin amines are available as powerful synthetic intermediates for a number of important reactions i. S2, 53. 

Organotin phosphines, arsines, stibines and bismuthines are known, and are exemplified, together with some of the commoner organotin amines in Table 10. 

The structures of organotin amines and alkoxides are tetrahedral, as expected. Organotin alkoxides and phenoxides are prepared from reaction with alcohols and alkali metal alkoxides or phenoxides with the organotin halide. Most of the published reactions occur in the liquid phase. For instance, the dimethoxide is formed from reaction of dibutyltin dichloride in methanol at 0°C in 98% yield. ... 

The reaction is of practical importance in the vulcanization of siUcone mbbers (see Rubber compounding). Linear hydroxy-terrninated polydimethyl siloxanes are conveniently cross-linked by reaction with methyldiethoxysilane or triethoxysilane [998-30-1]. Catalysts are amines, carboxyflc acid salts of divalent metals such as Zn, Sn, Pb, Fe, Ba, and Ca, and organotin compounds. Hydroxy-terrninated polysiloxanes react with Si—H-containing polysiloxanes to... 

Although inhibitors are deliberately added to the silicone formulation to control cure rate, unwanted cure inhibition can be caused by other species that react to form strong complexes with the platinum catalyst. Most notable of these undesired inhibitors include organotin and other organometallic compounds, sulfur, polysulfides, polysulfones or other sulfur-containing materials, amines, urethanes or amine-containing materials, unsaturated hydrocarbons in plasticizers, and some solder flux residues. 

Crompton [21] has reviewed the use of electrochemical methods in the determination of phenolic and amine antioxidants, organic peroxides, organotin heat stabilisers, metallic stearates and some inorganic anions (such as bromide, iodide and thiocyanate) in the 1950s/1960s (Table 8.75). The electrochemical detector is generally operated in tandem with a universal, nonselective detector, so that a more general sample analysis can be obtained than is possible with the electrochemical detector alone. 

In the single-stage production of polyurethanes, di-, tri-, or polyisocyanates are mixed directly with molecules containing two or more reactive hydrogen atoms, such as diols, diamines, and dicarboxylic acids. We typically increase the reaction rate by adding amine or organotin based catalysts. The reaction normally occurs rapidly, evolving much heat. In order to ensure... 

Catalysts Catalysts are widely used for PU manufacture. Sometimes a combination of two or three catalysts is required to obtain the desired balance of reaction rates between compounds of differing active hydrogen activity. Metal compounds, especially organotin compounds, are much more efficient catalysts than tertiary amines for the -OH/NCO reaction. In addition to more commonly used dibutyltin(IV) dilaurate, dibutyltin(IV) diacetate, dialkyltin(IV) oxide or salts of divalent fin with a variety of carboxylic acids such as stannous octoate, hexoate and naphthenate etc. are available for this purpose. Combination of tin catalysts with tertiary amines has been reported to lead to a synergistic increase in catalytic activity. 

Iodomethyl)trimethyltin, 150 Organotin reagents, 150 Homoallylic amines 3- Acetoxy-2-tributylstannylmethyl-1 -pro-pene, 3... 

---