... Telephone: 01438 768179. Fax: 01438 764242. E-mail: matthew.d.walker@gsk.com. ... Our initial attempts to synthesise 5,8-dichloroisoquinoline 11 were carried out on up to 20 g scale via the Pommerantz−Fritsch reaction. ... entry, conditions a, product b (%), 4-NO 2 isomer (%). ...