Naphthoate chiral

Triflates of phenols are carbonylated to form aromatic esters by using PhjP[328]. The reaction is 500 times faster if dppp is used[329]. This reaction is a good preparative method for benzoates from phenols and naphthoates (473) from naphthols. Carbonylation of the bis-triflate of axially chiral 1,1 -binaphthyl-2,2 -diol (474) using dppp was claimed to give the monocarboxy-late 475(330]. However, the optically pure dicarboxylate 476 is obtained under similar conditions[331]. The use of 4.4 equiv. of a hindered amine (ethyldiisopropylamine) is crucial for the dicarbonylation. The use of more or less than 4.4 equiv. of the amine gives the monoester 475. 

It should be noted that in most cases it is Cu-eatalyzed asymmetric oxidative biaryl homo-coupling reactions that are deseribed. On the contrary, successful examples of asymmetric oxidative biaryl eross-coupling reactions are rare. Habaue and co-workers discussed a highly eross-selective oxidative biaryl coupling between 3-hydroxy-2-naphthoates and 2-naphthols without ester functionality by a chiral Cu-BOX catalyst.The reactions proceed in a highly cross-eoupling selective manner with moderate enantioselectivity (up to 70% ee) (Scheme 3.7). Later, it was found that Lewis acids such as... 

The effect of amine ligands in copper(I)-catalyzed chemose-lective amide carbamoylation has been studied. Catalytic asymmetric synthesis of binaphthol derivatives is also reported by aerobic oxidative coupling of 3-hydroxy-2-naphthoates with chiral diamine-copper complexes (eq 15). ... 

---