53  5,744,650  54  20.  The  process  of  claim  19  wherein  the  organic  nitrogen  compound  is  benzimidazole  or  benzotriazole.  * * * * *  19.  The  process  of  claim  18  wherein  the  organic  nitrogen  compound  is  selected  from the  group  consisting  of  diazoles,  triazoles.  diazines  and  triazines.  18.  The  process  of  claim  16  wherein  phosphorus  acidic  compound  present  in the  reaction  product  fluid  is  scavenged  by an  organic  nitrogen  compound  that is  also  present  in said  reaction  product  fluid and  wherein  at least  some  amount  of  the  phosphorus  acidic  compound  of the  conversion  products  of the  reaction  between  said  phosphorus  acidic  compound  and said  organic  nitrogen  compound  are also  neutralized  and  removed  by the  aqueous  buffer  solution  treatment.  17.  The  process  of  claim  16  wherein  the  aqueous  buffer  solution  comprises  a  mixture  of salts  of  oxyacids  having  a  pH of  4 to 9.  14.  The  process  of  claim  1  wherein  said  metal› organopolyphosphite  ligand  complex  catalyst  comprises  rhodium  complexed  with  an  organopolyphosphite  ligand  represented  by the  formula:  1fi.  The  process  of  claim  10  wherein  phosphorus  acidic  compound  present  in the  reaction  product  fluid  of the  hydroformylation  process  is  treated  with an  aqueous  buffer  solution.  wherein  X  represents  a  substituted  or  unsubstituted  divalent  hydrocarbon  bridging  radical  containing  from  2 to 40  carbon  atoms,  each  R 1  is the  same  or  different  and  represents  a  divalent  hydrocarbon  radical  containing  from  4 to 40  carbon  atoms.  and each  R $^{2 }$is the  same  or  different  and  represents  a  substituted  or  unsubstituted  monovalent  hydrocarbon  radical  containing  from  1 to 24  carbon  atoms.  13.  The  process  of  claim  1  wherein  said  reaction  product  fluid  contains  a  homogeneous  or  heterogeneous  metal› organopolyphosphite  ligand  complex  catalyst  or at  least  a  portion  of said  reaction  product  fluid  contacts  a  fixed  het› erogeneous  metal-organopolyphosphite  ligand  complex  catalyst  during  said  hydroformylation  process.  12.  The  process  of  claim  5  wherein  the  organomonophos› phite  ligand  has (a)  a  coordination  strength  with  respect  to  the metal  of said  metal-organopolyphosphite  ligand  com- plex  catalyst  less than  carbon  monoxide  and  (b)  a  coordi› nation  strength  with  respect  to the  metal  of said  metal› organopolyphosphite  ligand  complex  catalyst  less than  the  organopolyphosphite  ligand  of said  metal› organopolyphosphite  ligand  complex  catalyst.  11.  The  process  of  claim  3  wherein  the  temperature  difference  between  reaction  product  fluid  temperature  and  inlet coolant  temperature  is less  than about  20°  C.  10.  The  process  of  claim  9  wherein  the  organomonophos› phite  ligand  is  hydrolyzed  to a  phosphorus  acidic  compound  comprising  a  hydroxy  alkyl  phosphonic  acid.  9.  The  process  of  claim  5  in  which  the  organomonophos› phite  ligand  is  treated  with  water,  a  weakly  acidic  compound,  or both  water  and  a  weakly  acidic  compound.  8.  The  process  of  claim  1  which  comprises  a  hydroformylation,  hydroacylation  (intramolecular  and  intermolecular).  hydrocyanation,  hydroamidation,  hydroesterification,  aminolysis,  alcoholysis,  carbonylation,  isomerization  or  transfer  hydrogenation  process.  15.  The  process  of  claim  14  wherein  said  metal- organopolyphosphite  ligand  complex  catalyst  comprises  rhodium  complexed  with  an  organopolyphosphite  ligand  having  the  formula  selected  from:  wherein  X  represents  a  substituted  or  unsubstituted  n-valent  organic  bridging  radical  containing  from  2 to  40  carbon  atoms,  each  R 1  is the  same  or  different  and  represents  a  divalent  organic  radical  containing  from  4 to  40  carbon  atoms.  each  R 2  is the  same  or  different  and  represents  a  substituted  or  unsubstituted  monovalent  hydrocarbon  radical  containing  from  1 to 24  carbon  atoms,  wherein  a and  b can  be the  same  or  different  and each  have  a  value  of 0 to  6.  with  the  proviso  that the  sum of  a+b is  2 to 6  and n  equals  a+b.  7. A  hydroformylation  process  which  comprises  reacting  one or  more  olefinic  unsaturated  compounds  with carbon  monoxide  and  hydrogen  in the  presence  of a  metal› organopolyphosphite  ligand  complex  catalyst  and  optionally  free  organopolyphosphite  ligand  to  produce  a  reaction  prod› uct fluid  comprising  one or  more  aldehydes,  and in  which  said  reaction  product  fluid  contains  at  least  some  organo› monophosphite  ligand  formed  during  said  hydroformylation  process,  wherein  said  hydroformylation  process  is con› ducted  at a  carbon  monoxide  partial  pressure  sufficient  to  prevent  and/or  lessen  coordination  of the  organomonophos› phite  ligand  with  said  metal-organopolyphosphite  ligand  complex  catalyst  0  O-R2  I  \  I  R 1  P-0-X-O-P  \I  \  0  O-R2 