We studied the methyltrioxorhenium (MTO)-CH 2 Cl 2 /H 2 O 2 biphasic system for epoxidizing soybean oil. The reactions were optimized (reactant ratio, time, and temperature), which resulted in a better performance (higher conversion and selectivity) than those described in the literature. Total doublebond conversion and 95% selectivity were obtained in 2 h at room temperature. Furthermore, it was possible to reach desired epoxidation degrees by changing the oxidant and MTO amounts. The rhenium-epoxidized soybean oil remained stable in the absence of stabilizers for up to 30 d when stored at mild conditions.

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Reações de hidroformilação foram realizadas com oleato de metila grau técnico e óleo de soja usando [RhH(CO)(PPh 3) 3 ] e [RhCl 3 .3H 2 O] (ligação dupla/Rh = 745) como precursores catalíticos, modificados ou não por trifenilfosfina. O complexo [RhH(CO)(PPh 3) 3 ] levou a 100% de conversão e 80-91% de produtos hidroformilados em 4 h para ambos substratos, sob condições reacionais brandas (100 o C, 40 bar, CO/H 2 = 2:1, ligante/Rh = 10:1). Verificou-se a rápida isomerização do óleo de soja, produzindo isomeros trans e dienos conjugados, porém sem prejuízo à hidroformilação. A reação do óleo de soja com [RhCl 3 .3H 2 O] puro, produz somente dienos conjugados, mas quando esse precursor foi modificado com trifenilfosfina (ligante/Rh = 10:1), nenhuma reação foi observada. Curiosamente, cristais amarelos correspondente ao complexo [Rh(Cl)(CO)(PPh 3) 2 ] foram quantitativamente isolados ao final da reação. Hydroformylation experiments were performed with technical-grade methyl oleate (MO) and soybean oil (SO) using [RhH(CO)(PPh 3) 3 ] and [RhCl 3 .3H 2 O] (double bond/Rh = 745) as catalyst precursors modified or not by triphenylphosphine. [RhH(CO)(PPh 3) 3 ] shows 100% conversion and 80-91% selectivity to aldehydes in only 4h for both substrates under mild conditions (100 °C, 40 bar, CO/H 2 = 2:1, ligand/Rh = 10:1). Despite the rapid isomerisation of the soybean oil, producing trans isomers and conjugated dienes, no effects were observed on its further conversion to aldehydes. The reaction of soybean oil conducted with pure [RhCl 3 .3H 2 O] produced only conjugated dienes, and when this precursor was modified with triphenylphosphine (ligand/Rh = 10:1) no reaction was observed at all. Curiously, yellow crystals corresponding to the complex [Rh(Cl)(CO)(PPh 3) 2 ] were quantitatively isolated at the end of the reaction .

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