5-Chloro-8-nitro-4 -quinazolinone

A 52% recrystalllized yield of the 8-nitro product 47 was reported from the nitration of 5-chloro-4(3/7)-quinazoli-none 46 <2005BMC5613>, although it is probable that some the 6-nitro isomer was also produced, as nitration of the analogous 5-fluoro-4(377)-quinazolinone gives a 4 1 mixture of the 6- and 8-nitro derivatives <1991JHC1459>. 

Quinazolinediones nitrate similarly to the quinazolinones, and thus 7-chloro-2,4-(l//,3 )-quinazolinedione 48 gave a 20 1 mixture of the 6- and 8-nitro derivatives 49 and 50 when treated with 60% HNO3 attd cone. H2SO4 at room temperature, but only a 10 1 mixture when fuming HNO3 was used <20010PD426>. 

Alkoxylation in the benzene ring of quinazolines and quinazolinones is readily achieved in the presence of an ortho-nitro group, and even in the absence of a nitro group, displacement of fluorine is still quite facile. Examples of haloquinazolines to have been alkoxylated include 5-chloro-8-nitro-4(3//)-quinazolinone 187 <2005BMC5613>, 7-chloro-6-nitro-4(377)-quinazolinone 188 <1996JME267>, 4-arylamino-7-fluoro-6-nitroquinazolines 189... 

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