“…Tests of thermal esterification under basic conditions have been performed separately; acetic acid is esterified, in 25% yield after 44 h at 100 8C, by an excess of methanol in the presence of 1 equiv. Formate ester synthesis by CO 2 hydrogenation in the absence of base has also been observed [45,64,74,84]. The yield of methyl formate from CO 2 is optimum at a temperature which is sufficiently high to allow substantial esterification, but not so high that the hydrogenation catalyst is deactivated.…”