1H-Cyclopropa[b]naphthalene (7) is converted into a range of 6p 5-atom-substituted methylidene derivs. I [R1 = 2-thienyl, R2 = H (12e), 2-thienyl, Ph; R1 = H, R2 = 2-furyl, N-methylpyrrol-2-yl, ferrocenyl], the pyridyl analogs I (R1 = H, R2 = 2- or 4-pyridyl), and the phenylsulfanyl analog I [R1 = Ph, R2 = 4-(p-tolylthio)phenyl] by way of 9 1,1-disilyl deriv. and Peterson olefination in an improved procedure. The spectroscopic properties of the compds. are reported and their behavior as possible luminophores assessed. Crystal structures of dimethylaminophenyl derivs. and thienyl deriv. 12e are presented. The permanent dipole moments of three I have been measured.