Organotin amines preparation

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. 

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. ... 

Cellulose can be modified with organostannane chlorides, such as dibutyl or triphenyl derivatives [91,92], or with organotin halides in the presence of bisethylenediamine copper(II) hydroxide [93]. Epoxy-activated cellulose was prepared by reacting cellulose acetate fibers with sodium methoxide, followed by reacting it with epichlorohydrin in DMSO. This epoxy-activated cellulose has proved to be a useful intermediate to react with substances containing active hydrogen, such as amine, amino acid, or carboxylic acids [94], as shown in Fig. 3. Epoxidized cellulose has also been converted to a thiol derivative via reduction of a thiosulfate intermediate [95], and sulfoethylcellu-[ose has been obtained from sodium chloroethanesulfonate [96]. Cellulose... 

The reaction of organotin halides with metal or ammonium carboxylates (equation 13-4 M = Na, K, Tl, Ag, or R3NH+) can be carried out in a solvent such as acetone or carbon tetrachloride, but it is more convenient to prepare the salt in situ by adding the acid to a solution of sodium in an alcohol.10 The sodium carboxylate is formed in a finely-divided form, and then reacts readily with the equivalent amount of the organotin chloride. Alternatively the reaction can be carried out by slowly adding a tertiary amine to a solution of the acid and tin chloride in a solvent such as benzene.10... 

S tanny lphosphincs can be prepared by treating an organotin halide with a metallo-phosphine, or with a hydridophosphine in the presence of a tertiary amine, or by acidoly-sis of a stannylamine with a phosphine. Some examples of these reactions are given in equations 16-70,67 16-71,68 and 16-72.69 Stannylphosphines containing a PH group, like the corresponding amines, disproportionate unless they are stabilised by steric hindrance. 

Complexes of organotin with amidines have been found to be excellent catalysts for the preparation of polyurethane foams, which do not have the disadvantage of any amine odor and, in addition, delayed onset of the isocyanate-hydroxyl reaction An example of a mercapto-delayed organotin catalyst is 2,2,4,4-tetrakis(alkyl)- l,3,2,4-dithia-stannetane.55 Amine salts of amino acids, tertiary amino acids, and tertiary amino acid-nitrile compositions, have been found to be effective as delayed action catalysts for polyurethane synthesis. They are particularly effective when used in combination with an organometallic compound, such as an organotin. ... 

Hydrolytically stable organotin compounds are also being prepared with sulfonic acids. " These di-alkyltin and trialkyltin sulfonates can be used in combination with t -amines as catalysts in the preparation of polyurethane foams. 

Di-n-butyltin catalysts are being used in the preparation of polyurethane foams. Most polyurethane foams utilize aromatic isocyanates such as toluene diisocyanate (TDI) or diphenylmethane diisocyanate (MDI) as the isocyanate, and a polyester or polyether polyols as the coreactant. Tertiary amine catalysts are used to accelerate the reaction with water and formation of the carbon dioxide blowing agent. To achieve a controlled rate of reaction with the polyol, an organotin catalyst can be used. Polyurethane foams are not only applied in place, but are also cast in a factory as slabstocks. These foam slabs are then cut for use in car seats, mattresses, or home furnishings. DBTDL is an excellent catalyst in high resiliency slabstock foams. DBTDL shows an excellent reaction profile for this application replacement for DBTDL in such an end-use is difficult and requires a substantial reformulation of the foam. 

Aminations of alkyl halides and carboxylic esters are performed with organotin amides, which are also employed for the preparation of enamines (eq (118)) [113],... 

In a third method for the preparation of compounds of formula (R3Sn)3N, lithium nitride is used. A reaction between this compound and organotin halides was first noted in 1961 (80), but the first compound prepared by this method, tris(trimethylstannyl)amine, was isolated only in 1964 (81). 

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