2,2 -Biaryls tetrahydro

In contrast, the enantiomerically pure, nitrogen-free compound (4.S )-l,2,3,4-tetrahydro-4,7,8-trimethyl-6-naphthalenol is oxidatively coupled using potassium hexacyanoferrate(III) to give the (/ -biaryl derivative (P)-4 with a very high atropisomer selectivity the corresponding (Af)-isomer is not detected in the reaction mixture5,6. 

A successful simple appHcation of the quinazolinone aimelation is the short step synthesis of rutecarpine 16, an indolopyridoquinazoline alkaloid of Evodia rutaecarpa, from 2,3,4,9-tetrahydro-lH-j8-carbolin-l-one 80 via 2-azidobenzoyl derivative 81 (Scheme 18) [222]. Even after Kametani s practical iminoketene/amides condensation synthesis [227,228], many other synthetic routes to 16 and related systems utilizing Fischer indole synthesis [223-225] or cyclocondensation [65,226,229,230], etc. have been developed among these syntheses, above quinazolinone annelation route is one of the most facile and concise one. Recently very concise Pd-assisted biaryl coupling route to 16 as well as to luotonin A (26) and B (27) has been developed by Harayama et al. [231,232] (see Sect. 3.5). 

---