This is exactly what people now know as the structural formula of cinnamic acid! There is a big circle in this structural formula, which is benzene ring. If you know that this structural formula was given before Kekule discovered the structure of benzene, you will be surprised! It turns out that before the great Kekule discovered the structure of benzene ring, Joseph Lauschmidt, an unknown Austrian middle school teacher, knew the structure of benzene ring as early as 186 1. Later, people saw in the first volume of chemical research written by Lauschmitt that Lauschmitt used this structural formula to obtain the correct structural formula of many organic compounds, many of which contain benzene rings, and cinnamic acid is only one of them.
Lauschmitt not only made outstanding contributions to the development of organic chemistry, but also should be mentioned that he was the first person to determine Avon Gadereau constant. Therefore, there is not a middle school student in Europe who does not call Avon Gadereau constant Loschmidt constant, and the symbol of this physical quantity is mostly expressed by the initial letter L of Loschmidt in Europe.
It is worth mentioning that Richard Anschotz told us that it was Lauschmitt, not Kekule, who discovered the structure of benzene. Admirably, he is a student in Kekule! Besides the structural problems of benzene, he also told people that tetravalent carbon was not first proposed by Kekule in 1865, but the Scottish chemist Archibald Scott Couper died young in 1858.
It should be repeated that Lauschmitt's position is very different from that of the great Kekule-he is only an Austrian middle school teacher. Historical materials do not say whether the great Kekule read Lauschmitt's articles in advance, but one thing is certain: Lauschmitt's benzene ring structure diagram must have been before Kekule dreamed.