The photochemical rearrangement of 1,1,2,2-tetraphenylethane. A di-π-ethane reaction.

Solvent effects on the visible circular dichroism of copper (II) compleses with N,N-dialkylated amino acids

“…490 nm and a shoulder near 600 nm. 3 In Figure 1 the CD spectrum of bis(L-A,7V-diethyl-aalaninato)copper(II) (compound I) in benzene solution is seen to exhibit two positive bands. Both the visible spectrum and the CD spectrum of I in benzene may be (1) J. M. Tsangaris and R. B. Martin, J. Amer.…”

“…> ), X = CH2, NH, 0, etc. = 1,2,3... methane rearrangement.2 Recently we have discovered that the photolysis of 1,1,2,2-tetraphenylethane leads to a di-7r-ethane reaction,3 a discovery which suggested that the di--methane rearrangement might be only the first in a homologous series of -interaction processes.1 We have now investigated the photochemical reactions of 1,1,3,3-tetraphenylpropane (1), 1,1,4,4-tetraphenylbutane (2), and 1,1,5,5tetraphenylpentane (3),4 compounds capable of experiencing the di^-propane (compound 1), di-butane (2), and di^-pentane (3) reactions, and wish to report that the first of these processes is observed while the latter two do not take place in this series of compounds. These and earlier observations3•5 establish that -interaction processes in the tetraphenylalkanes can occur when the systems are separated by one or more atoms but that there is a limit to the number of separating atoms which will allow reaction to proceed.…”