Di-tert-butyl dicarbonate → Naphthalene

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-bromoaminonaphthalene (5.0 g) and di-tert-butyldicarbonate (5.9 g) in 100 mL toluene was heated at 70° C. for 15 hours, cooled to room temperature and the volatiles removed in vacuo. The residue was dissolved in ethyl acetate, washed with 0.1M HCl and brine, dried (MgSO4) and the volatiles removed in vacuo. Recrystallization of the residue from hot petroleum ether provided LXXXIV. 4-Vinylpyridine (0.86 mL) was added to a suspension of LXXXIV (2.0 g) in 5 mL of triethylamine, followed by palladium (II) acetate (0.014 g) and tri-ortho-tolylphosphine (0.038 g). The mixture was heated at 110° C. for four hours, cooled to room temperature, diluted with water and ethyl acetate. The organic layer was washed with brine, dried (MgSO4) and the volatiles removed in vacuo. Purification of the residue by flash chromatography using 50% ethyl acetate in hexanes as the eluent and concentration of the product-rich fractions in vacuo provided naphthalene LXXXV. A solution of LXXXV (0.34 g) in 10 mL TFA was stirred one hour and the volatiles removed in vacuo to provided LXXXVI. LXXXVI and LXVII (Example 1) were reacted according to Method B to provide 6, m.p. 203° C. (dec).

Provenance & Evidence