Catalyst compositions for hydroformylation and methods of use thereof

Abstract

Disclosed are highly active cationic cobalt phosphine complexes, both mono- and bimetallic, that can catalyze hydroformylation reactions. The disclosed catalysts can be utilized in methods that provide reaction processes that are hundreds of times faster than high pressure HCo(CO) 4 or phosphine-modified HCo(CO) 3 (PR 3 ) catalysts and operate at considerably lower pressures and temperatures. Also disclosed are methods of hydroformylation using the described transition metal complexes. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

1 . A compound of formula I or a salt, solvate, or stereoisomer thereof; 
       
         
           
           
               
               
           
         
         wherein in formula I: 
         X is selected from the group consisting of O, NR 3 , and CR 9 R 10 , wherein R 8 , R 9 , and R 10  can be the same or different and are each independently selected from the group consisting of H, C 1 -C 5  alkyl, C 2 -C 5  alkenyl, C 1 -C 5  alkoxy, C 1 -C 20  alcohol, C 3 -C 6  cycloalkyl, C 3 -C 6  cycloalkoxy, C 6 -C 10  aryl, C 6 -C 10  alkaryl, C 6 -C 10  aralkyl, C 4 -C 10  heteroaryl, and combinations thereof; or optionally R 9  and R 10  can together form a C 3 -C 6  cycloalkyl ring; 
         each occurrence of Y independently represents a divalent linking group selected from the group consisting of C 1 -C 6  alkyl, C 1 -C 6  alkenyl, C 6 -C 14  aryl, C 4 -C 14  heteroaryl, O, NR 4 , and combinations thereof; 
         each occurrence of R 1 , R 2 , R 3 , and R 4  is independently selected from the group consisting of C 1 -C 20  alkyl, C 1 -C 8  alkoxy, C 1 -C 20  alcohol, C 3 -C 6  cycloalkyl, C 3 -C 6  cycloalkoxy, C 6 -C 10  aryl, C 6 -C 10  alkaryl, C 6 -C 10  aralkyl, C 4 -C 10  heteroaryl, and combinations thereof; or R 2  and R 3  may optionally be joined together to form a ring; or optionally one of R 1  and one of either R 9  or R 10  may together form a ring; 
         M 1  and M 2  each independently represent a transition metal selected from the group consisting of Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir, and Pt, and M 1  and M 2  can be the same or different; 
         n is an integer between 0 and 4, wherein the value of the number n for the ligand L 1  depends on the transition metal M 1  and is selected such that the transition metal M 1  has 14, 15, 16, 17, 18, or 19 valence electrons; 
         m is an integer between 0 and 4, wherein the value of the number m for the ligand L 2  depends on the transition metal M 2  and is selected such that the transition metal M 2  has 14, 15, 16, 17, 18, or 19 valence electrons; 
         p is an integer between 0 and 4; and 
         L 1  and L 2  can be the same or different and each occurrence is independently selected from the group consisting of trialkylphosphine, tricycloalkylphosphine, diethyl ether, tetrahydrofuran, H 2 O, CO, acetylacetonate, acetate, C 1 -C 6  alkoxide, acetonitrile, cyclooctadiene, N(R 11 ) 3 , N(R 11 ) 2 , C 1 -C 6  alkyl, C 4 -C 10  heteroaryl, C 4 -C 10  heterocycle, H, Cl, Br, I, and F; wherein R 11  is H, alkyl, cyclcoalkyl, heteroalkyl, or heterocyclic. 
       
     
     
         2 . The compound of  claim 1 , wherein X is CR 9 R 10 . 
     
     
         3 . The compound of  claim 1 , wherein R 2  and R 3  are each C 1 -C 6  alkyl. 
     
     
         4 . The compound of  claim 1 , wherein R 2  and R 3  are each ethyl. 
     
     
         5 . The compound of  claim 1 , wherein R 1  is phenyl. 
     
     
         6 . The compound of  claim 1 , wherein Y is 1,2-phenylene. 
     
     
         7 . The compound of  claim 1 , wherein M 1  and M 2  are each independently selected from the group consisting of Co and Rh. 
     
     
         8 . The compound of  claim 1 , wherein p is 2. 
     
     
         9 . The compound of  claim 1 , wherein L 1  and L 2  are each independently selected from the group consisting of acetoacetonate, acetonitrile, pyridine, and cyclooctadiene. 
     
     
         10 . The compound of  claim 1 , wherein the compound of formula I is selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
     
     
         11 . A compound of formula (II), or a salt or stereoisomer thereof; 
       
         
           
           
               
               
           
         
         wherein in formula (II): 
         each occurrence of R 5  and R 6  is independently selected from the group consisting of C 1 -C 20  alkyl, C 1 -C 8  alkoxy, C 1 -C 20  alcohol, C 3 -C 6  cycloalkyl, C 3 -C 6  cycloalkoxy, C 6 -C 10  aryl, C 6 -C 10  alkaryl, C 6 -C 10  aralkyl, or combinations thereof; or R 5  and R 6  may optionally be joined together to form a ring; 
         Z represents a divalent linking group selected from the group consisting of C 1 -C 6  alkyl, C 1 -C 6  alkenyl, C 6 -C 14  aryl, C 4 -C 14  heteroaryl, O, NR 4 , and combinations thereof; 
         M is a transition metal selected from the group consisting of Fe, Co, Ni, Cu, Ru, Rh, Pd, Ir, and Pt; 
         q is an integer between 0 and 4; 
         o is an integer between 0 and 4, wherein the value of the number o for the ligand L depends on the transition metal M and is selected such that the transition metal M has 14, 15, 16, 17, 18, or 19 valence electrons; and 
         each occurrence of L can be the same or different and is selected from the group consisting of trialkylphosphine, tricycloalkylphosphine, diethyl ether, tetrahydrofuran, H 2 O, CO, acetylacetonate, acetate, C 1 -C 6  alkoxide, acetonitrile, cyclooctadiene, N(R 11 ) 3 , N(R 11 ) 2 , C 1 -C 6  alkyl, C 4 -C 10  heteroaryl, C 4 -C 10  heterocycle, H, Cl, Br, I, and F; wherein R 11  is H, alkyl, cyclcoalkyl, heteroalkyl, or heterocyclic. 
       
     
     
         12 . The compound of  claim 11 , wherein M is Rh or Co. 
     
     
         13 . The compound of  claim 11 , wherein L is acetylacetonate. 
     
     
         14 . The compound of  claim 11 , wherein R 5  and R 6  are each C 1 -C 6  alkyl, phenyl, or cycloalkyl; each of which may be optionally substituted. 
     
     
         15 . The compound of  claim 11 , wherein Z is 1,2-phenylene, 1,2-ethylene, or 1,3-propylene. 
     
     
         16 . The compound of  claim 11 , wherein q is 1. 
     
     
         17 . The compound of  claim 11 , wherein the compound of formula (II) is selected from the group consisting of 
       
         
           
           
               
               
           
         
       
     
     
         18 . A method of preparing an aldehyde-containing compound, the method comprising contacting an alkene-containing compound with the compound of  claim 1  in the presence of hydrogen (H 2 ) and carbon monoxide (CO), whereby the alkene is converted to an aldehyde. 
     
     
         19 . The method of  claim 18 , wherein the concentration of the compound is between 10 −6  M and 10 −2  M. 
     
     
         20 . The method of  claim 18 , wherein H 2  and CO are present in a ratio ranging from about 40:60 to about 60:40.