Observed

Pronunciation

Verb

1. observed

   (past of observe)
   Aldrichimica Acta Volume 30 No 4 (pdf) from Sigma-Aldrich
2. N-substituted pyrroles are much less reactive than the other 5-membered 1,3-dienes; no reaction was observed between N-(trimethylsilyl) pyrrole or N-benzylpyrrole with Smith’s diene (4) under thermal or high pressure (4 days at 14 kbar) conditions, even in the presence of Lewis acids.