Naphthalene tetrachlorides and related compounds. Part 11. trans-1,1,3,4-Tetrachlorotetralin-2-one, its hydrate, and related compounds

X-Ray crystallographic analysis of 1,1,3,4-tetrachlorotetralin-2,2-diol has shown that this compound is the trans-isomer, which can be reversibly dehydrated to give trans-1,1,3,4-tetrachlorotetralin-2-one of previously unknown configuration, produced nearly quantitatively by chlorination of 2-naphthol in acetic acid. The 1H and 13C spectra of these compounds are reported; most of the angular-dependent coupling constants accord with expectations, the value of 3J(13C-1, 1H-3) being low, probably because the coupling path includes a carbonyl carbon atom. The rather high value of 3J(H-3, H-4) is discussed. The properties of some related ketodichlorides and ketotetrachlorides are reported.