A USEFUL MODIFICATION OF THE ATTACHED PROTON TEST C-13 NMR EXPERIMENT- UNAMBIGUOUS PEAK ASSIGNMENTS FOR CARBONS WITH LARGE (1)J(CH) VALUES

We have developed an extension of the APT C-13 NMR experiment which di fferentiates tetracoordinate methine carbons and hexacoordinate 2-carb oranyl carbons in complex organic molecules bearing o-carboranyl funct ionalities, as well as discriminating between pairs of carbons such as methylenes and terminal alkynes. The differences in the (1)J(CH) of e ach carbon results in modified intensities in APT experiments using a 7.5 msec and a 10 msec delay. Comparing the spectra from these two exp eriments definitively assigns the peaks to the appropriate carbon, yie lding information often only obtainable from 2D experiments. Copyright (C) 1996 Elsevier Science Ltd