Tri-n-butylantimony oxide

More recently Nicholas and Gmitter [23] prepared heat-resistant, rigid poly-isocyanurate foams and Sandler [24] reported on a similar process to prepare heat-resistant adhesives for aluminum. The trimerization agents reported by Sandler [24] were various metal salts and organometallic compoimds such as tri-n-butylantimony oxide [25] as shown in Table X. 

Trimerization. Phenyl isocyanate allowed to stand at room temp, in the presence of tri-n-butylantimony oxide in a stoppered flask with occasional swirling until after ca. 1 hr. the mixture is completely solid phenyl isocyanurate. Y 94%, F. e., also with triisobutylarsenic oxide, and in solvents such as heptane or dimethyl sulfoxide, s. S. Herbstman, J. Org. Ghem. 30, 1259 (1965) f. catalysts cf. B. D. Beitchman, Ind. Eng. Ghem., Prod. Res. Develop. 5, 35 (1966). 

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