SI-29 AND C-13 NMR-SPECTRA OF TERT-BUTYLDIMETHYLSILYL DERIVATIVES OF AMINO-ACIDS

Si-29 and C-13 MMR chemical shifts are reported for tert-butyldimethyl silyl (TBDMS) derivatives of ten common amino acids. The Si-29 chemica l shifts of TBDMS derivatives of various functionalities encountered f all into distinct spectral regions. The Si-29 chemical shifts correlat e linearly (r = 0.999) with the Si-29 shifts reported earlier for the trimethylsilyl (TMS) derivatives of the same amino acids, the Si-29 ch emical shift values in the TBDMS derivatives being larger than those i n the TMS derivatives (in Si-N groups this downfiled shift varies betw een 3.8 and 5.8 ppm and in Si-O groups between 1.4 and 1.7 ppm).