The molecular and crystal structures of two derivatives containing 8,11-dioxa[4.3.3]propellane moiety:
8,11-dioxa[3,4-(4
0
-methylbenzo)]-[4.3.3]propellane and 8,11-dioxa[3,4-(4
0
-
tert
-butylbenzo)]-[4.3.3]pro-
pellane, were determined and compared with those found for 1,2,4,5-bis{8
0
,11
0
-dioxa[4.3.3]propel-
la(3
0
,4
0
)}benzene. The discussion of the most stable conformation of cyclohexene and tetrahydrofurane
rings for isolated 8,11-dioxa(3,4-benzo)]-[4.3.3]propellane molecule was made using the DFT calcula-
tions. The results were compared with those performed for tetraline and 2,2,3,3-tetramethyltetraline.
8,11-Dioxa[3,4-(4
0
-methylbenzo)]-[4.3.3]propellane is important as a reference compound because the
unsubstituted 8,11-dioxa(3,4-benzo)-[4.3.3]propellane cannot be obtained in the form of crystalline
phase suitable for X-ray diffraction.
1
H NMR spectroscopic analysis showed that the methyl group does
not induce expected splitting of the appropriate signals, observed in the case of
tert
-butyl derivative.