Biaryl methanols, formation

Similar conditions have promoted five-, six-, and seven-membered ring formations by intramolecular cyclization of arylboron compounds onto ketones (Scheme 31). " Biaryl methanols can be obtained from aryl aldehydes by Rh-catalysed addition of an aryl ring bearing an Al-direcfing group ortho to the activated Cyclization... 

The pharmacological versatility of this general substitution strategy is further illustrated by diazonium coupling of 14 with 2-nitrobenzenediazonium chloride to produce biarylal-dehyde 18. Formation of the oxime with hydroxylamine is followed by dehydration to the nitrile. Reaction with anhydrous methanolic hydrogen chloride leads to imino ether and addition-elimination of ammonia leads to the antidepressant amid-ine, nitrafudam (20). ... 

The efficiency of the mixed electrolysis between phenol and arene components can be substantially ameliorated and is the subject of current research. The application of very pure HFIP in this electrolysis led to loss of selectivity and dramatically inferior yield. Therefore, an optimized protocol was developed which requires a specific amount of water or methanol as mediator in the electrolyte. This allows the formation of the biaryl 53 in exclusive selectivity and in almost 70% isolated yield. 

Irradiation of methanolic solutions of N,N-dimethylanilines containing tetracyanoethylene (TCNE) leads to the formation of biaryls (50), e.g. [161] (Ohashi et al., 1977a Ohashi et al., 1979c). Benzo(a)pyrene, the powerful... 

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