Expanded Porphyrin-like Structures Based on Twinned Triphenylenes

Abstract

Triphenylene twins are intriguing structures, and those bridged through their 3,6-positions by dipyrromethene units give a new class of macrocycles that can be viewed as rigid, expanded porphyrin derivatives in which coplanarity is enforced in a formally antiaromatic π system. Somewhat surprisingly, however, macrocyclization leads to significant overall stabilization of the dipyrromethene chromophores.

Benziporphyrins, a unique platform for exploring the aromatic characteristics of porphyrinoid systems

“…102 Expanded porphyrinoids 202 and 203 with linking triphenylene units have been reported (Fig. 103 However, in this case the spectroscopic data are consistent with a nonaromatic system. 103 These porphyrinoids are also structurally related to phenanthriporphyrin (Scheme 72).…”

“…When 197a was treated sequentially with palladium(II) chloride and potassium carbonate, metalation and ring fusion took place to give the organometallic derivative 201 (Scheme 80). 103 These porphyrinoids are also structurally related to phenanthriporphyrin (Scheme 72). 102 Expanded porphyrinoids 202 and 203 with linking triphenylene units have been reported (Fig.…”

“…This species takes on a Möbius topology and the NMR spectrum shows the presence of a significant diatropic ring current. 103 However, NMR data could not be obtained because the macrocycle is highly aggregated in solution. 14) and these introduce a rigidified tetracarbaporphyrinoid core.…”

“…14) and these introduce a rigidified tetracarbaporphyrinoid core. 103 Other examples of expanded porphyrinoids incorporating benzene subunits include oligopyrrolic macrocycles such as 204 with linking phenylene units (Fig. Porphyrinoid 202 possesses a 30π electron delocalization pathway and the UV-vis spectrum indicates that this is a neutral aromatic compound.…”

Incorporation of a Phenanthrene Subunit into a Sapphyrin Framework: Synthesis of Expanded Aceneporphyrinoids

“…Those systemsa re to date represented by azulisapphyrin, [17,18] benzocarbasapphyrin, [17,18] and dibenzoamethyrin, [19] carbasapphyr-in, [20] N-confused heterosapphyrins, [21] doubly N-confused sapphyrin derivatives, [22] expanded benziporphyrinoids, [23][24][25][26][27][28][29] and macrocycles with incorporated triphenylene motifs. [30] In this contribution we presentt he synthesis and properties of expandeda ceneporphyrinoids-32-hetero-5,6-dimethoxyphenanthrisapphyrinsa nd 32-thia-5,6-dioxophenanthrisapphyrin. Those macrocycles are structurally relatedtophenanthriporphyrin [11] or tetraarylsapphyrins [31] and might be classified as dicarbasapphyrins (Scheme 1).…”