In 1849,
Charles Blachford Mansfield rectified
coal tar and identified fractions which he hypothesized to be
cumole and
cymole. The latter fraction boiled slightly above 170°C and had specific density of 0.857. In 1862,
Warren De la Rue and Hugo Müller (1833-1915) proposed the term
pseudocumole for the fractions heavier than
xylole. When three years later American chemist
Cyrus Warren (1824-1891) attempted to reproduce Mansfield's results, he determined that the oil boiling at 170° has the same formula as cumole, not cymole, and suggested to name it
isocumole. The structure of the compound was determined by Th. Ernst and
Wilhelm Rudolph Fittig, who first prepared it from
bromoxylene and
iodomethane in 1866 by a
Wurtz–Fittig reaction developed two years earlier. In the next year, Fittig et al. adopted the pseudocumol terminology, in 1869 Fittig and B. Wackenroder proved that the fraction is a mixture of
mesitylene with another trimethylbenzene, for which the name of pseudocumol was retained, and in 1886 showed that the
third trimethylbenzene he discovered earlier is also present. == Production ==