A trishomocubyl helical tubuland diol inclusion host

Abstract

All three isomers of 4,7-dimethylpentacyclo[6.3.0.0^2,6.0^3,10.0^5,9] undecane-4,7-diol have been prepared and their X-ray structures determined as part of a crystal engineering study into the prediction of new inclusion hosts. The syn,syn-isomer 9 forms a double-stranded hydrogen-bonded lattice type [C₁₃H₁₈O₂, P2₁/c, a 6.3005(5), b 22.372(1), c 7.5313(6)Å, β 96.748(4)°, Z 4, R 0.052] and the anti,syn isomer 10 forms a hydrogen-bonded layer lattice [P2₁/c, a12.005(1), b 6.3979(7), c14.955(1)Å, β112.767(3)°, Z 4, R 0.045]. In contrast, the anti,anti-isomer 11 is a new member of the helical tubuland diol host family [(C₁₃H₁₈O₂)₃·(C₃D₆O)_1.2, P3₁21, a12.4957(6), c 7.3076(3), Z 1, R 0.039] containing parallel guest-containing canals with trefoil-shaped cross-section of area 25.4 Ų.