Cyclic arylene ethynylene hexamer 1, composed of alternating 2,7-anthrylene ethynylene units and meta-phenylene ethynylene units, was synthesized. It shows C symmetry and possesses a flat and rigid conformation with a large equilateral triangle-like cavity. Macrocycle 1 self-associates through π-π stacking interactions between the anthracene-containing macrocyclic aromatic cores with indefinite-association constant K =6980 m in CDCl at 303 K. Macrocycle 1 also self-assembles into π-stacked nanofibers in the drop-cast film.

The synthesis of a cyclohexa‐2,7‐(4,5‐diaryl)anthrylene ethynylene (1) was achieved for the first time by using 1,8‐diaryl‐3,6‐diborylanthracene and 1,8‐diaryl‐3,6‐diiodoanthracene as key synthetic intermediates. Macrocycle 1 possesses a planar conformation of approximately D6h symmetry, because of the triple‐bond linker between the anthracene units at the 2,7‐positions. It was confirmed that macrocycle 1, bearing bulky substituents at the outer peripheral positions, behaves as a monomeric form in solution without π‐stacking self‐association. Macrocycle 1 has an inner‐cavity size that allows specific inclusion of [9]cycloparaphenylene ([9]CPP), but not [8]CPP or [10]CPP, through an aromatic edge‐to‐face CH‐π interaction.

The synthesis of a cyclohexa‐2,7‐(4,5‐diaryl)anthrylene ethynylene (1) was achieved for the first time by using 1,8‐diaryl‐3,6‐diborylanthracene and 1,8‐diaryl‐3,6‐diiodoanthracene as key synthetic intermediates. Macrocycle 1 possesses a planar conformation of approximately D6h symmetry, because of the triple‐bond linker between the anthracene units at the 2,7‐positions. It was confirmed that macrocycle 1, bearing bulky substituents at the outer peripheral positions, behaves as a monomeric form in solution without π‐stacking self‐association. Macrocycle 1 has an inner‐cavity size that allows specific inclusion of [9]cycloparaphenylene ([9]CPP), but not [8]CPP or [10]CPP, through an aromatic edge‐to‐face CH‐π interaction.

Iridium-catalyzed direct tetraborylation of anthracene to give 1,3,5,7-tetrakis(Bpin)anthracene 5 was achieved by using a combination of [Ir(OMe)(COD)] 2 and tmphen as the catalyst.Compound 5 was applied to the synthesis of 1,3,5,7-tetraarylanthracenes 7 as a new molecular entity. The latter showed long fluorescence lifetime in the solid state. Keywords: C-H borylation | Anthracene | Cross-couplingAnthracene derivatives as π-electronic cores are useful building blocks for materials used in optoelectronics 1 and for organic semiconductors.2 To date, most studies on anthracene derivatives have focused on 9,10-or 2,6-diarylanthracene derivatives and 9,10-or 2,6-bis(arylethynyl)anthracene derivatives. To develop the properties of anthracene derivatives further, the synthesis of tetraarylanthracene derivatives at various positions is considered to be an important area with significant potential. The syntheses of 2,6,9,10-tetraarylanthracene derivatives 2b,3 and 1,4,5,8-tetraarylanthracenes 4 have been achieved. However, to our knowledge, the synthesis of 1,3,5,7-tetraarylanthracenes is without precedent.Iridium-catalyzed direct CH borylation of aromatic compounds using bis(pinacolato)diboron (B 2 pin 2 ) is a very useful reaction for the synthesis of arylboronic acid pinacol esters, 5 which are reagents for the SuzukiMiyaura cross-coupling reaction.6 Under typical reaction conditions involving a combination of [Ir(OMe)(COD)] 2 and 4,4¤-di-tert-butyl-2,2¤-bipyridine (dtbpy) as the catalyst, direct CH borylation of aromatic compounds proceeds with sterically driven regioselectivity; this usually means that the position ortho to the substituent on the same ring and the peri-position on the adjacent ring do not react (ortho/peri-prohibition).5 This is also the case for linear acenes.7 Thus, Ir-catalyzed direct diborylation of anthracene under the typical reaction conditions selectively produces a 1:1 mixture of 2,6-and 2,7-bis(Bpin)anthracenes 1 and 2 (Chart 1).7c Recently, Scott and Marder developed multiborylation of polyaromatic hydrocarbons such as pyrene and corannulene at the peri-positions by using a combination of [Ir(OMe)(COD)] 2 and 4,4¤-dimethyl-2,2¤-bipyridine (dmbpy) as catalyst with a catalytic amount of t-BuOK.8 It is known that 3,4,7,8-tetramethyl-1,10-phenanthroline (tmphen) is an electronrich ligand that can enhance the activity of the resulting Ircatalyst. 9 Here, we report the Ir-catalyzed direct tetraborylation of anthracene to give 1,3,5,7-tetrakis(Bpin)anthracene 5 (Chart 1) by using a combination of [Ir(OMe)(COD)] 2 and tmphen as a catalyst. We also describe the application of 5 to the synthesis of 1,3,5,7-tetraarylanthracenes 7 as a new molecular entity; the latter showed long fluorescence lifetime in the solid state. 10The reaction of anthracene (0.1 M) and B 2 pin 2 (5 equiv) in the presence of [Ir(OMe)(COD)] 2 (20 mol %) and tmphen (40 mol %) in cyclohexane at 80°C for 48 h gave a mixture of 1,3,5,7-tetrakis(Bpin)anthracene 5, 1,3,7-tris(Bpin)anthracene 3, and 1,3,6-tris(Bpin)anthracene 4 in ...

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