Unsymmetrical Photodimerization of a 9-Aminomethylanthracene in the Crystalline Salt

Abstract

By the salt formation with particular nonaromatic dicarboxylic acids, rapid and selective photodimerization of 9-(N,N-dimethylaminomethyl)anthracene (1) was accomplished in the solid state. For instance, the salt with trans,trans-muconic acid or acetylenedicarboxylic acid was led quantitatively to the 9,10:4',1' photodimer usy-ht-2, the first example of the unsymmetrical [4+4] photodimerization of anthracene in the solid state. The reactions were rationalized by the relevant C...C distances between the reacting carbons.

Crystal structures and photoreactivity of trans- and cis-valerophenone diperoxides

“…4] photocyclodimerization by varying the crystal structures through formation of two-component crystals [25,26]. As a modifier component, hydrogen-bonding intermolecular linkers (e.g., gauche 1,2-diamine, phthalic acid, and oxalic acid) [39][40][41][42][43][44], small molecules (e.g., NH 3 and divalent metal) [26,45], and relatively small and planar molecules (e.g., imidazole, trans,trans-muconic acid, and acetylenedicarboxylic acid) [45,46] were employed. In the course of these studies, two-component crystals were frequently found to be more loosely packed than one-component crystals and hence two-component crystals appeared to undergo decreased topochemical restriction to molecular motions.…”

Optical switches with biplanemers obtained by intramolecular photocycloaddition reactions of tethered arenes

“…The dimerization leads in both cases to the formation of three s bonds (Scheme 18). 31,[54][55][56] Apart from the structures 42, which represent head-to-head dimers, head-to-tail dimers can be formed, provided that the tethers are long enough. 57 Sterically congested bis(9-anthryl)methane derivatives, such as 2,2-bis(9-anthryl)lactic acid esters, do not show a [4p + 4p] cycloaddition reaction.…”

Photoinduced Reactions of Radical Ions via Charge Separation

“…184 In the crystal structure, the bond length of the newly formed C-C bond (C6-C6 ) is 1.629(2) Å, which is much longer than normal C-C single bonds, indicating severe distortion of this compound. 184 The synthesis of another type of anthracene dimer such as lepidopterene has previously been carried out by intramolecular Diels-Alder reaction of 9-anthrylmethyl a, p-dimer, [185][186][187][188][189] dehalogenation of 9-chloromethylanthracene, 190,191 oxidation of 9-methylanthracene with copper(II)/ peroxy-disulfate, 192 photolysis of 9-(N ,Ndimethylamino)-anthracene, 193 9-(phenoxymethyl) anthracene, 194 and 9-anthrcenylmethylsulfides and selenides. 195 The one-pot synthesis of the lepidopterene from the corresponding anthracene has been made possbile using Acr + -Mes as a photocatalyst as shown in Scheme 17.…”