Synthesis, Resolution, and Determination of Absolute Configuration of a Vaulted 2,2′‐Binaphthol and a Vaulted 3,3′‐Biphenanthrol (VAPOL).

Two methods for the synthesis of vaulted biaryls were developed involving the reactions of carbene complexes with alkynes and the [2 + 2] cycloaddition of ketenes. The final step in the synthesis of 3,3‘-diphenyl-[2,2‘-binaphthalene]-1,1‘-diol (39) and 2,2‘-diphenyl-[3,3‘-biphenanthrene]-4,4‘-diol (47) (VAPOL) was phenol coupling of the 3-phenyl-1-naphthol (14) and the 2-phenyl-4-phenanthrol (28), respectively. The naphthol 14 could be prepared from the thermolysis of phenylacetyl chloride in the presence of phenylacetylene or from the benzannulation of the pentacarbonyl(phenylmethoxymethylene)chromium(0) (15) with phenylacetylene which upon an acetylative workup gives O-acetyl-4-methoxy-2-phenyl-1-naphthol (16). The reductive cleavage of the acetoxy group in 16 was unexpectedly affected by aluminum chloride and ethanethiol which were used to cleave the methyl ether. In a similar manner, the phenanthrol 28 could either be prepared from the 1-naphthylacetyl chloride (30) or pentacarbonyl(1-naphthylmethoxym...