[marcinosss]

Hi,

I'm going to do reaction: Ph2C=NCH2P(O)(OPh)2 + Br(CH2)2CO2CH2Ph 
I want generate anion of Ph2C=NCH2P(O)(OPh)2 using KHMDS.
How should I use KHMDS? I think first I add KHMDS to Ph2C=NCH2P(O)(OPh)2 -78^oC, then (past 2h?) I add Br(CH2)2CO2CH2Ph. To end reaction I add NH₄Cl. Am I right? Is it necessary using inert atmosphere?

Thanks for any suggestions.

[MissPhosgene]

Use inert atmosphere and keep the reaction water free. If you don't the end result will probably be a mess.

I would add the phosphonate to KHMDS with an addition funnel instead of the other way around. Make a solution of known concentration which is in excess of what you need, cannula the necessary amount into a dry addition funnel under inert atmosphere and then add that to the base.