3- Methyl-2-butanol, aluminum complex

Aluminum porphyrins first came to attention with the discovery that the simple alkyl complex Al(TPP)Et was capable of activating CO2 under atmospheric pressure. Both irradiation with visible light and addition of 1-methylimidazole were required for the reaction, which was proposed to proceed by initial coordination of the base to aluminum. The aluminum porphyrin containing direct product of CO2 insertion was not isolated, but was proposed on the basis of IR data to be (TPP)A10C(0)Et, which was then treated with HCl gas, presumably liberating propanoic acid, subsequently isolated as the butyl or methyl ester after reaction with 1-butanol or diazomethane, respectively [Eq. (5)]. Insertion of CO2 into the Al—C bond of an ethylaluminum phthalocyanine complex has also been reported. ... 

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