NMR INVESTIGATIONS ON DIASTEREOMERIC MIXTURES OF BIS(DIALKOXYTHIOPHOSPHORYL) SULFANES AND -POLYSULFANES CONTAINING sec. BUTOXY GROUPS. ASSIGNMENT OF ³¹P, ¹³C AND ¹H NMR SIGNALS IN A MIXTURE OF SEVEN DIASTEREOMERS USING SHIFT-CORRELATED 2D NMR SPECTRA

Abstract

Synthesizing compounds of the structure

diastereomeric mixtures were obtained. If possible, the ³¹P chemical shifts and P[sbnd]P coupling constants of the individual diastereomers were determined from the 31P NMR spectra of these diastereomeric mixtures.

In addition, the mixture of the seven diastereomers of bis(di-sec. butoxythiophosphoryl)disulfane was analyzed using shift-correlated ³¹P[sbnd]³¹P {¹H}, ¹³C-³¹P {¹H}, ¹³C-¹H {³¹P} and ¹H-¹H {³¹P) 2D NMR spectra. In this way, the ³¹P, ¹³C and ¹H chemical shifts and the corresponding coupling constants were assigned to the diastereomers.

The appearance of regions of similar chemical shift into which the ¹H, ¹³C and ³¹P signals of identical atoms or atom groups can be classified is characteristic of all the diastereomeric mixtures investigated. These regions can be explained mainly by the symmetry relations of a molecule moiety (sBuO)₂P(S)S[sbnd].

Key Words:

• ³¹P NMR
• 2D NMR
• organophosphorus sulfanes
• diastereomers
• P[sbnd]P coupling constants.