The ^1H and ^3^1P NMR spectra of 1, 3-diphosphorylpropenes prepared by a new reaction were studied. Homo 2DJ and hetero 2D COSY have been employed in distinguishing J(HH) and J(PH), and the signals of the isomeric mixtures. ^3J(HH) of vinyl groups confirmed the regioselectivity, showing the trans form to be the main products (～ 95%). In compounds except 1, 2 and 7, different positions of double bond give rise to the existence of two isomers, A and B, with the latter ～10% in excess. In 1 and 2, four identical R groups were divided in to two groups because of the presence of a double bond, and the same groups attached to the different achiral P atom are non- equivalent as well. These are confirmed by the spectra of hydrogenation products. However, δ~p of the two P atoms show different behavior with -P(O)Ph(OR) at the lowest field. ^4J(PP) among these compounds were obtained, J~c~i~s(9Hz)>J~t~r~a~n~s(7Hz). The reduced values from those of hydrogenation products confirm the enhancement of P-P coupling by π electrons.

Key words: PROPENE, PHOSPHORYL, NUCLEAR MAGNETIC RESONANCE, REGIOSELECTIVITY, COUPLING REACTION, CIS-FORM, TRANSFORM