Hydroxylated organotins

Nakamura reported that the ultrasound-promoted reaction of tin hydride with alkenes in the presence of air results in the addition of stannyl and hydroxyl groups across the double bond (hydroxystannylation) (Scheme 16). This procedure is the first example of the conversion of alkenes to hydroxylated organotin compounds... 

Sun G-X, J-J Zhong (2006) Mechanism of augmentation of organotin decomposition by ferripyochelin formation of hydroxyl radical and organotin-iron ternary complex. Appl Environ Microbiol 72 7264-7269. 

S. David and S. Hanessian, Regioselective manipulation of hydroxyl groups via organotin derivatives. Tetrahedron 41 643 (1983). 

Organosilicon and Organotin Chemistry Relevant to Hydroxyl Protection 349... 

The reaction of butyltin trichloride with l-(2-methyl-2,3-dihydrobenzotriazol-2-yl)-propan-2-one gives an organotin complex that was formulated as containing the [BuSn(OH)Cl3]2 anion " . However, a reinvestigation of the crystal structure of this complex reveals a neutral hydroxyl-bridged aqua-butyldichlorotin hydroxide dimer that is linked to four 2-methylbenzothiazole molecules by short hydrogen bonds " . 

RaCH—OH with configurational retention (equation S). This finding may have applications in the synthesis of various hydroxylated natural products based on organotin intermediates. 

Organotin compounds are effective catalysts for the isocyanate-hydroxyl reaction. Tin catalysts have a slight odour, and low amounts are required to achieve a high reaction rate. Examples of organotin catalysts are stannous octoate, stannous oleate, dibutyltin dilaurate and dibutyltin di-2-ethylhexoate. They are often used in conjunction with small concentrations of antioxidants such as tertiary-butyl catechol resorcinol and tartaric acid. 

A number of organotin polyesters, polyamides, polythiols, polyethers, and polyaminoesters have been synthesized from dialkyltin halides with dicarboxylic acids, diols, diamines, dithiols, urea, thiourea, amino acids, and hydroxyl acids involving polycondensation reactions. These polymers have potential applications as thermostabilizers for PVC. 

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. ... 

Polymerization in such systems is based on the reaction of isocyanate with hydroxyl groups to form the urethane linkage-OrganometaI Iic compounds (especially organotin) are often used to catalyze this reaction in commercial applications such as Reaction Injection Molding. Formation of elastomers with good mechanical properties is dependent on both reaction kinetics and development of two phase morphology. 

Relatively little basic information has been published regarding the kinetics of phenol-formaldehyde intermediates, especially of phenols, methylol phenols, benzyl alcohol and benzylic ethers with isocyanates. Due to the fact that a typical resole contains both phenolic and benzylic hydroxyl groups, it was of interest to determine their reactivity toward isocyanates in the presence of various catalysts, as well as the effect of substitution on their reactivity. This investigation describes the kinetics of model phenols and model benzyl alcohols with phenyl isocyanate catalyzed with either a tertiary amine (dimethylcyclo-hexylamine, DMCHA) or an organotin catalyst, dibutyltin dilaurate (DBTDL) in either dioxane or dimethylformamide solution. 

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