text: With the lone exception of the bis(trifluoromethyl) derivative, the dominant reaction of phosphinous acids is tautomerization:
  :PROH  →  OPRH
  Even the pentafluorophenyl compound P(CF)OH is unstable with respect to the phosphine oxide.
  Although phosphinous acids are rare, their P-bonded coordination complexes are well established, e.g.  Mo(CO)P(OH).