[2591-86-8] · C6H11NO · N-Formylpiperidine · (MW 113.18)
Physical Data: bp 222 °C; d 1.09 g cm-3.
Form Supplied in: liquid; widely available.
Analysis of Reagent Purity: IR, NMR.
Handling, Storage, and Precautions: toxic; irritant.
N-Formylpiperidine (1) is a good formylating agent for certain organometallics. Carbaldehydes can be obtained by reacting (1) with organolithium or Grignard reagents (eq 1).1
N-Trifluoromethylpiperidine will result on reaction of (1) with Sulfur Tetrafluoride and Potassium Fluoride (eq 2).2
Chloromethyleneiminium ions with different counterions can be easily prepared from (1).3 The chloromethyleneiminium ion generated from (1) reacts with thioamides to give various products depending on the reaction conditions (eqs 3-5).4,5 N,N-Disubstituted thioamides undergo condensation to give thioenamides (2) (eq 3).4 Under similar reaction conditions, primary thioamides yield either the nitrile (3) (eq 4) or the salt (4) (eq 5).5
Daniel L. Comins & Sajan P. Joseph
North Carolina State University, Raleigh, NC, USA