4-tert-Butyl-3',4'-bis-(4-methyl-phen-yl)-3,4-dihydro-1H,4'H-spiro-[naphthalene-2,5'-[1,2]oxazol]-1-one.

In the title compound, C(30)H(31)NO(2), the cyclo-hexa-none ring in the naphthalene fused-ring system adopts a half-chair conformation, presumably due to conjugation of the benzene ring. The naphthalene ring system makes dihedral angles of 86.63†(7), 65.15†(8) and 63.18†(8)° with respect to the two methyl-benzene planes and the 1,2-oxazole ring system. Inter-molecular C-H⋯O and C-H⋯N hydrogen bonding and C-H⋯π inter-actions stabilize the crystal structure. The H atoms of the two methyl groups of the methyl-phenyl groups are disordered over two positions with equal occupancies.