2-Bromo-1,4-dimethoxynaphthalene → 2-(1,4-Dimethoxy-3-naphthylcarbonyl)-5-(2-methyldioxolan-2-yl)-6-oxa-bicyclo[3,2,1]octan-7-one

Participants

Reaction Steps

Following the method described in Example 4, a solution of 3.2 g of 1,4-dimethoxy-3-bromo-naphthalene in anhydrous tetrahydrofuran was treated at -78° C. with n-butyllithium and then added to a solution in anhydrous tetrahydrofuran of 2.7 g of the compound prepared in Example 3. After silica gel column purification 2.8 g of the title compound was obtained (65% yield) m/z 426 (M+.): IR (film): 1780 cm-1 (C=O, five membered ring lactone), 1670 cm-1 (C=O, benzylic ketone); PMR (CDCl3): inter alia: δ1.4 (s, CH3), 3.85 (s, two OCH3), 3.9 (s, --O--CH2 ----CH2 --O--), 6.9 (s, aromatic H) and 7.4-8.4 (m, four aromatic H).

Provenance & Evidence