Dibutyltin dichloride

Prepa.ra.tlon, Diorganotin dichlorides are the usual precursors for all other diorganotin compounds three primary methods of manufacture are practiced. Dibutyltin dichloride is manufactured by Kocheshkov redistribution from cmde tetrabutyltin and stannic chloride and usually is cataly2ed with a few tenths of a percent aluminum trichloride ... 

Detection and result The chromatogram was freed from mobile phase (heated to 110°C for 30 min) and then exposed to bromine vapor for 1 h in a chamber, after blowing off excess bromine from the layer it was immersed for 1 s in the reagent solution. On drying in air dibutyltin dilaurate hRf 25 — 30), dibutyltin dichloride (kR( 25 — 30), dioctyltin oxide (hR( 40), tributyltin oxide (hRf 80), tributyltin chloride (hRf 80) and tetrabutyltin (hRf 85-90) produced persistent blue zones on a yellow ochre background (Fig. 1). 

Fig. 1 Chromatogram of organotin compounds. Dibutyltin dilaurate (1), dibutyltin dichloride (2), dioctyltin oxide (3), tributyltin oxide (4), tributyltin chloride (5), tetrabutyltin (6).

Fig. 2 Absorption scans of chromatograms with 50, 100 and 200 ng dibutyltin dichloride per chromatogram zone.

Two approaches for the synthesis of allyl(alkyl)- and allyl(aryl)tin halides are thermolysis of halo(alkyl)tin ethers derived from tertiary homoallylic alcohols, and transmetalation of other allylstannanes. For example, dibutyl(-2-propenyl)tin chloride has been prepared by healing dibutyl(di-2-propenyl)stannane with dibutyltin dichloride42, and by thermolysis of mixtures of 2,3-dimethyl-5-hexen-3-ol or 2-methyl-4-penten-2-ol and tetrabutyl-l,3-dichlorodistannox-ane39. Alternatively dibutyltin dichloride and (dibutyl)(dimethoxy)tin were mixed to provide (dibutyl)(methoxy)tin chloride which was heated with 2,2,3-trimethyl-5-hexen-3-ol40. 

Both allylstannane transmetalation and thermolysis of homoallyl stannoxanes have been used to prepare 2-butenyltin halides as (E)j(Z) mixtures44-45. The reaction between 2-butenyl-(tributyl)stannane and dibutyltin dichloride initially provides dibutyl(l-methyl-2-propenyl)tin chloride as the kinetic product by an SE2 process, but this isomerizes under the reaction conditions to give a mixture containing the (Z)- and (E)-2-butenyl isomers46. 

The lower trialkyltin hydroxides and oxides, which are usually readily interconverted, have been characterized by IR and Mossbauer spectroscopy (212). The dimer of di-n-butyltin oxide (Bu2SnO)2 has been reported to be formed as a crystalline solid when dibutyltin dichloride is hydrolyzed with ammonium hydroxide (213). 

Dimethyltin dichloride (hRf 15-20), trimethyltin chloride (h/ f 55-60), dibutyltin dichloride (h/ f 70-75) and tributyltin methoxide (h/ f 80-85) appeared in long-wavelength UV light (X = 365 nm) as yellow fluorescent chromatogram zones on a dark background. The detection limits (calculated as Sn) lay between 5 and 10 ng (dimethyltin dichloride, dibutyltin dichloride, tributyltin methoxide) and 50 ng (trimethyltin chloride) substance per chromatogram zone. 

Fig. 1 Fluorescence scan of a chromatogram track with 100 ng substance (calculated as Sn) each per chromatogram zone 1 = dimethyltin dichloride, 2 = trimethyltin chloride, 3 = dibutyltin dichloride, 4 = tributyltin methoxide.

Immunotoxicity, consistently effects on thymus weight but also measures of functional immunotoxicity, is demonstrated for dibutyltin and mono- and dioctylins. A NOAEL could not be determined for dibutyltin, but the lowest dose reported as causing effects was 2.5 mg/kg body weight per day (as dibutyltin dichloride). 

Monomethyltin trichloride Dimethyltin dichloride Monobutyltin trichloride Dibutyltin dichloride Monooctyltin trichloride Dioctyltin dichloride... 

Sn -I- 2RI R2Snl2 (where R is the alkyl group and I is the anion). Methyltin stabilizers are produced by direct synthesis in the United States. Dibutyltin dichloride is manufactured from crude tetrabutyltin and tin tetrachloride and is usually catalysed with aluminium trichloride (Blunden Evans, 1989 Gaver, 1997 Thoonen et al, 2001). 

The observed BCFs for dibutyltin dichloride in round crucian carp (Carassius carassius grandoculis) muscle, vertebra, liver, and kidney tissue were 12, 46,... 

Administration of dibutyltin dichloride intraperito-neally to rats led to the formation of butyl(3-hydroxy-butyl)tm, butyl(4-hydroxybutyl)tin, and monobutyltin. The major metabolite (buty 1(3-hydroxybutyl)tin) was distributed to the kidney at a relatively high concentration compared with the other metabolites, and its concentration increased with time. Butyl(4-hydroxybutyl)tin was found in urine only. The parent compound and other metabolites were detected in the brain (Ishizaka et al., 1989). Dibutyltin diacetate was destarmylated by 14% within 90 h following a single oral dose in mice at 1.1 mg/kg body weight, with several butyltin derivatives found in the liver or faeces (Boyer, 1989). 

Arakawa et al. (1983) reported that dibutyltin elimination from kidney, liver, spleen, and thymus, following cessation of dietary dosing with dibutyltin dichloride for 1 week at 100 mg/kg diet, was rapid, with half-lives for each organ at several days. Merkord et al. 

Dermal exposure of rats to doses of dimethyltin dichloride at 80 mg/kg body weight produced dermal necrosis with the formation of black scars the same dose of dibutyltin dichloride produced little surface damage to the skin together with subcutaneous oedema. Dioctyltin dichloride produced no skin lesions (Barnes Stoner,... 

Animal data consistently show dibutyltin dichloride to cause dose-dependent developmental toxicity, such as fetal deaths, birth defects, and reductions in fetal weight. 

A study on Wistar rats by Farr et al. (2001) showed no maternal toxicity at doses up to 5 mg/kg body weight for dibutyltin dichloride signs of maternal toxicity — reduced body weight gain, decreased food consumption, and thymus weight — were observed at 10 mg/kg body weight. No teratogenic effects were seen at 10 mg/kg... 

In recent in vitro studies, an aromatase inhibiting effect on human placental microsomal extracts has been demonstrated with both tributyltin chloride and dibutyltin dichloride (Heidrich et al, 2001 Cooke,... 

MMTC, monomethyltin trichloride DMTC, dimethyltin dichloride MBTC, monobutyltin trichloride DBTC, dibutyltin dichloride MOT, monooctyltin MOTC, monooctyltin trichloride MOT(IOMA), monooctyltin bis(isooctyl mercaptoacetate) DOT, dioctyltin DOTC, dioctyltin dichloride DOT(IOMA), dioctyltin bis(isooctyl mercaptoacetate)... 

Hamasaki et al. (1992) reported that monobutyltin oxide, monobutyltin trichloride, and dibutyltin dichloride showed high SOS-inducing potency in the SOS chromotest with iiic/rerrc/rra co/r PQ 37. Dibutyltin dichloride and dimethyltin dichloride were also recognized as producing DNA damage by the rec-assay in Bacillus subtilis H 17 Rec and M45 Rec. Li et al. 

Dibutyltin dichloride induced acute pancreatitis and bile duct lesions in rats, depending on dose (6 and 8 mg/kg body weight intravenously) and time (1-24 weeks) (Merkord Hennighausen, 1989 Merkord et al., 1997, 1999 Sparmann et al., 2001). The lesions in the pancreas developed into a pancreatic fibrosis, and the lesions in the liver into liver cirrhosis. A single intravenous administration of dibutyltin dichloride at 4 mg/kg body weight induced a mild interstitial pancreatitis after 2 days (Merkord et al., 2001). Repeated administration of dibutyltin dichloride (4 mg/kg body weight intravenously) to rats at intervals of 3 weeks induced acute interstitial pancreatitis and, after 9-12 weeks, a pancreatic fibrosis and liver lesions (intrahepatic bile duct hyperplasia) (Merkord et al, 2001). 

In vivo and in vitro studies on the differentiation and proliferation of immature rat thymus subsets have shown that dibutyltin dichloride reduces the production of CD4 CD8 and mature single-positive thymocyte proliferation by selectively inhibiting immature CD4 CD8 thymocyte proliferation but without affecting the differentiation capacity of these cells, suggesting that thymocyte proliferation and differentiation are separately regulated processes (Pieters et al., 1993, 1994a,b, 1995). 

Additionally, mechanisms of immunosuppression by organotins have also focused on the role of apoptosis versus proliferation arrest. The apoptotic pathway followed by organotin compormds such as dibutyltin dichloride and tributyltin chloride at high doses is... 

Harazene A, Ema M (2003) Suppression of decidual cell respense induced by dibutyltin dichloride in pseudopregnant rats as a cause ef early embryenic loss. Reproductive Toxicology, 17(4) 393-399. 

Ishizaka T, Suzuki T, Salto Y (1989) Metabolism of dibutyltin dichloride in male rats. Journal of Agricultural and Food Chemistry, 37 1096-1101. 

Sterner W, Chibanguza G (1976) Acute inhalation toxicity of dibutyltin dichloride in rats, internationai Bio-Research, inc., March. 

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