A Systematic Investigation of Long-Range Couplings in the 1H NMR Spectra of Dimeric Indanones

 During the synthesis of methyl substituted indanones by intramolecular cyclization of 3-phenyl-propionic acids, dimerization led to by-products which can be considered as dimeric indanones. The proton NMR spectra of these compounds exhibit pronounced scalar couplings over up to seven bonds. A series of structures of the above type were investigated, and their NMR spectroscopic behaviour is discussed.