Selective hydrodeoxygenation of aromatic compounds

Abstract

Disclosed are methods of selective hydrodeoxygenation of aromatic compounds by using catalyst systems comprising N-heterocyclic carbene (NHC) and 4-pyridinol-derived pincer ligands and metal complexes containing these ligands.

1 - 18 . (canceled) 
     
     
         19 . A catalyst of formula (I): 
       
         
           
           
               
               
           
         
         wherein, 
         R 1  is hydrogen, OH, halogen, amine, C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, C 6 -C 14  aryloxy, C 3 -C 10  cycloalkyl, or C 3 -C 10  cycloalkenyl, wherein R 1  is optionally substituted with C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone, nitro, cyano, silyl, sulfo-oxo, sulfonyl, sulfone, sulfoxide, thiol, or phosphonyl; 
         each R 2  is, independent of the other, C 1 -C 10  alkyl, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, or C 1 -C 13  heteroaryl, wherein R 2  is optionally substituted with C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone, nitro, cyano, silyl, sulfo-oxo, sulfonyl, sulfone, sulfoxide, or thiol; 
         each R 3  and R 4  are, independent of the other, hydrogen, C 1 -C 10  alkyl, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, or C 1 -C 13  heteroaryl, wherein R 3  and R 4  are optionally substituted with C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone, nitro, cyano, silyl, sulfo-oxo, sulfonyl, sulfone, sulfoxide, or thiol, or R 3  and R 4  combine together with the atoms to which they are attached to form a cycloalkyl, cycloheteroaryl, aryl, or heteroaryl; 
         each R 16  and R 17  are, independent of the other, hydrogen, OH, halogen, amine, C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, C 6 -C 14  aryloxy, C 3 -C 10  cycloalkyl, or C 3 -C 10  cycloalkenyl, wherein each R 16  and R 15 , independent of the other, is optionally substituted with C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 2 -C 10  alkenyl, C 2 -C 10  alkynyl, C 6 -C 14  aryl, C 1 -C 13  heteroaryl, aldehyde, amino, carboxylic acid, ester, ether, halide, hydroxy, ketone, nitro, cyano, silyl, sulfo-oxo, sulfonyl, sulfone, sulfoxide, thiol, phosphonyl; 
         M is Ru or Ir; 
         each L is independently selected from Cl, Br, CH 3 CN, DMF, H 2 O, bipyridine, phenylpyridine, CO 2 , and a CNC-pincer ligand; and 
         n is 1, 2, or 3. 
       
     
     
         20 . The catalyst of  claim 19 , selected from 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         wherein R″ is methyl or phenyl, and X is Cl, Br, or CH 3 CN, wherein n=1 when X is Cl or Br, and n=2 when X is CH 3 CN. 
       
     
     
         21 . The catalyst of  claim 20 , wherein M is Ru. 
     
     
         22 . The catalyst of  claim 20 , wherein R 2  is independently selected from C 1 -C 10  alkyl, and C 6 -C 14  aryl. 
     
     
         23 . The catalyst of  claim 21 , wherein R 1  is hydrogen, OH, halogen, amine, C 1 -C 10  alkyl, C 1 -C 10  alkoxy, wherein R 1  is optionally substituted with C 1 -C 10  alkyl or C 6 -C 14  aryl. 
     
     
         24 . The catalyst of  claim 23 , wherein R 1  is C 1 -C 10  alkoxy. 
     
     
         25 . The catalyst of  claim 24 , wherein R 1  is methoxy. 
     
     
         26 . The catalyst of  claim 23 , wherein R 1  is amine substituted with C 1 -C 10  alkyl or C 6 -C 14  aryl. 
     
     
         27 . The catalyst of  claim 26 , wherein R 1  is dimethylamine or diphenylamine. 
     
     
         28 . The catalyst of  claim 21 , wherein R 16  and R 17  are, independent of the other, hydrogen, C 1 -C 10  alkyl, or C 1 -C 10  alkoxy. 
     
     
         29 . The catalyst of  claim 28 , wherein R 16  and R 17  are each hydrogen. 
     
     
         30 . The catalyst of  claim 21 , wherein R 3  and R 4  are each, independent of the other, hydrogen or C 1 -C 10  alkyl. 
     
     
         31 . The catalyst of  claim 21 , wherein R 3  and R 4  are each hydrogen. 
     
     
         32 . The catalyst of  claim 21 , wherein R 3  and R 4  combine together with the atoms to which they are attached to from an aryl or heteroaryl ring. 
     
     
         33 . The catalyst of  claim 21 , wherein each L is independently selected from Cl, Br, and CH 3 CN. 
     
     
         34 . The catalyst of  claim 20 , wherein M is Ir and R 2  is independently selected from C 1 -C 10  alkyl, and C 6 -C 14  aryl. 
     
     
         35 . The catalyst of  claim 20 , wherein M is Ir and R 1  is hydrogen, OH, halogen, amine, C 1 -C 10  alkyl, C 1 -C 10  alkoxy, wherein R 1  is optionally substituted with C 1 -C 10  alkyl or C 6 -C 14  aryl. 
     
     
         36 . The catalyst of  claim 20 , wherein M is Ir and R 16  and R 17  are, independent of the other hydrogen, C 1 -C 10  alkyl, or C 1 -C 10  alkoxy. 
     
     
         37 . The catalyst of  claim 20 , wherein M is Ir and R 3  and R 4  are each, independent of the other, hydrogen, C 1 -C 10  alkyl, or R 3  and R 4  combine together with the atoms to which they are attached to from an aryl or heteroaryl ring. 
     
     
         38 . The catalyst of  claim 20 , wherein M is Ir and each L is independently selected from Cl, Br, and CH 3 CN.