[Kaladiscope]

Dear colleagues,

I got two phosphorous spectras of two compounds. The first one is a P(NMe2)3 and the second one P(OCH2CH2OMe)3.

For the first compound I got a quintuplet. I guess that there are some P-H coupling with the protons of Methyl. But in the second case what I got is just a singlet, so no coupling between P-H. Is because of the oxygen? Or is something unexpected?

Thank you,

[discodermolide]

Dear colleagues,

I got two phosphorous spectras of two compounds. The first one is a P(NMe2)3 and the second one P(OCH2CH2OMe)3.

For the first compound I got a quintuplet. I guess that there are some P-H coupling with the protons of Methyl. But in the second case what I got is just a singlet, so no coupling between P-H. Is because of the oxygen? Or is something unexpected?

Thank you,

What are the 31P chemical shifts?

[Kaladiscope]

For P(NMe2)3, 10-13 ppm. This is a quintuplet.

For P(OCH2CH2OMe)3, 139 ppm. This is a singlet.

[discodermolide]

For P(NMe2)3, 10-13 ppm. This is a quintuplet.

For P(OCH2CH2OMe)3, 139 ppm. This is a singlet.

The shifts look ok but I can't explain the coupling, usually they are singlets because the proton signals are broad band decoupled.