Nickel pre-catalysts and related compositions and methods

Abstract

Described herein are nickel pre-catalysts and related compositions and methods. The nickel pre-catalysts may be activated to form catalysts which may be utilized in organic reactions.

1 . A pre-catalyst, comprising:
 a nickel (II) atom, wherein the nickel (II) atom is associated with at least one phosphine ligand; at least one aryl ligand; and at least one leaving group.   
     
     
         2 . The pre-catalyst of  claim 1 , wherein the pre-catalyst comprises two phosphine ligands. 
     
     
         3 . The pre-catalyst of  claim 1 , wherein the pre-catalyst comprises two phosphine ligands, one aryl ligand, and one leaving group. 
     
     
         4 - 6 . (canceled) 
     
     
         7 . The pre-catalyst of  claim 1 , wherein the pre-catalyst has the structure: 
       
         
           
           
               
               
           
         
         wherein each R 1  is independently optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted aryl, or any two R 1  may be joined together to form a ring; 
         Ar is the at least one aryl ligand, and LG is the at least one leaving group. 
       
     
     
         8 . The pre-catalyst of  claim 1 , wherein the pre-catalyst has the structure: 
       
         
           
           
               
               
           
         
         wherein each R 2  is independently optionally substituted alkyl, optionally substituted cycloalkyl, or optionally substituted aryl, or any two R 2  are joined together to form a ring; 
         each R 3  is —O—, optionally substituted alkylene, optionally substituted heteroalkylene, optionally substituted arylene, optionally substituted heteroarylene, or optionally substituted ferrocenylene; 
         n is 1, 2, 3, 4, 5, or 6; Ar is the at least one aryl ligand; and 
         LG is the at least one leaving group. 
       
     
     
         9 - 18 . (canceled) 
     
     
         19 . The pre-catalyst of  claim 1 , wherein the leaving group is selected from the group consisting of halo, OTs, and OMs. 
     
     
         20 . A method, comprising:
 activating a pre-catalyst as described in  claim 1  to form a catalyst.   
     
     
         21 . The method of  claim 20 , further comprising reacting an optionally substituted benzyl chloride with a terminal alkene in the presence of the catalyst. 
     
     
         22 . The method of  claim 20 , further comprising reacting a terminal alkene with an aldehyde and a silyl triflate in the presence of the catalyst. 
     
     
         23 . The method of  claim 20 , wherein the activating comprises reacting the pre-catalyst with an activating agent. 
     
     
         24 . The method of  claim 20 , wherein the pre-catalyst does not comprise cyclooctadiene. 
     
     
         25 . The method of  claim 20 , wherein the activating is carried out in the presence of oxygen. 
     
     
         26 . The method of  claim 20 , wherein the reaction is stereoselective via reaction of the external position of the terminal alkene. 
     
     
         27 . The method of  claim 20 , wherein the reaction is stereoselective via reaction of the internal position of the terminal alkene. 
     
     
         28 . The method of  claim 20 , wherein the benzyl chloride has the structure: 
       
         
           
           
               
               
           
         
       
       wherein each R 4  is independently halo, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkylene, optionally substituted aryl, optionally substituted —O-alkyl, —SO 2 -alkyl, —COOH, —COO-alkyl, or any two R 4  can be joined together to form a ring; and n is 0, 1, 2, 3, 4, or 5. 
     
     
         29 . The method of  claim 20 , wherein the terminal alkene has the structure: 
       
         
           
           
               
               
           
         
       
       wherein R 5  is optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkylene, optionally substituted heteroalkyl, optionally substituted alkyl-aryl, or optionally substituted aryl. 
     
     
         30 . The method of  claim 20 , wherein the product of the reaction between the optionally substituted benzyl chloride with a terminal alkene is: 
       
         
           
           
               
               
           
         
       
       wherein each R 4  is independently halo, optionally substituted alkyl, optionally substituted heteroalkyl, optionally substituted alkylene, optionally substituted aryl, optionally substituted —O-alkyl, —SO 2 -alkyl, —COOH, —COO-alkyl, or any two R 4  can be joined together to form a ring; n is 0, 1, 2, 3, 4, or 5; and R 5  is optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted alkylene, optionally substituted heteroalkyl, optionally substituted alkyl-aryl, or optionally substituted aryl.