Derivatives of this compound that unexpectedly form in solid crystals of cinnamic (“sih-NAM-ick”) acid spurred the development of the topochemical postulate. A derivative of this compound is the intermediate destroyed by retro-aldol cleavage in the de Mayo reaction. A dimerization that forms this compound is the simplest reaction that requires a Möbius twist on p orbitals so that there is one suprafacial and one antarafacial component. 1,4-diradicals recombine to form a derivative of this compound in a type II (“two”) Norrish reaction. (10[2])A metal replaces a carbon atom in this compound (10[1]-5[1])in the intermediate of olefin metathesis (“muh-TATH-uh-siss”). Under light, (10[1])but not heat, (-5[1])alkenes like thymine dimerize to form derivatives of this compound (-5[1])in a [2 + 2] (“two plus two”) cycloaddition. (10[2]-5[4])This compound has bond angles of 88 degrees because it puckers into (10[2])a butterfly (10[1])configuration to reduce ring strain. (10[1])For 10 points, (10[1])name this cyclic alkane containing four (10[1])carbons. (10[1])■END■ (10[6])