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D,)-Bis[cyclotriveratryleny1) [4), has been synthesized in racemic and optically active forms by stereospecific replication of a (C,)-subunit ; the absolute configuration of (+)-(4) was assigned from that of the (C,) -precursor. ALTHOUGH D,symmetry is readily accessible in octahedral tris(che1at e) metal complexes, organic molecules that belong to this point group are very uncommon.2 We report in this communication the synthesis of (D,)-bis(cyclotriveratry1enyl) (4), a new macrocage in which the chiral D, symmetry arises from the spatial arrangement of six equivalent achiral aromatic residues. Initial attempts to obtain the key compound (C3)cyclotriguaiacylene [ & ) -(2e) by acid-catalysed condensation of vanillyl alcohol (lc) only afforded intractable material, presumably owing to the presence of the free phenolic group.In contrast, the phenol-protected derivative (la) was found

The circular dichroism of chiral C3-cyclotriveratrylenes 2-12 in which the substitution patterns correspond to various combinations of RI and R2 = H , OH, 0-, and OAc, and 0-alkyl groups has been analyzed in light of the exciton theory, using the concept of spectroscopic moments. From the observed signs and intensities of the BZu couplets, a self-consistent set of polarization angles for this transition in the OH/O-alkyl ortho-disubstituted derivatives has been established. The spectroscopic moments of these substituents have been shown to increase on going from the bulkiest (O-i-C,H,) to the smallest (OH) group, very likely as a consequence of different equilibria between planar and nonplanar conformers. Finally, the experimental Bzu and BIu couplets have been satisfactorily reproduced in most of the cases studied by calculations based on the exciton approximation, with limited p-a configuration interaction.Cyclotriveratrylene (1) a n d its analogues devoid of bulky substituents ortho t o t h e nine-membered ring are rigid, coneshaped molecules t h a t exhibit stable optical activity a t ambient temperature when t h e achiral C,, symmetry of t h e parent com-pound is destroyed by appropriate substitution (e.g., when R l # RJ.' W i t h t h e exception of a C,-monobenzyl ether which was partially resolved in 1966 by Liittringhaus? all the optically active (1) Collet, A. In "Inclusion Compounds"; Atwood, J. L., Ed.; Academic

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