@article{SengeDahmsHoldtetal.2015,
  author    = {Senge, Mathias O. and Dahms, Katja and Holdt, Hans-J{\"u}rgen and Kelling, Alexandra},
  title     = {Porphyrin substituent regiochemistry, conformation and packing - the case of 5,10-diphenylporphyrin},
  series = {Zeitschrift f{\"u}r Naturforschung : B, Chemical sciences},
  volume    = {70},
  journal   = {Zeitschrift f{\"u}r Naturforschung : B, Chemical sciences},
  number    = {2},
  publisher = {De Gruyter},
  address   = {T{\"u}bingen},
  issn      = {0932-0776},
  doi       = {10.1515/znb-2014-0217},
  pages     = {119 -- 123},
  year      = {2015},
  abstract  = {5,10-Disubstituted porphyrins are more recent additions to the family of meso-substituted porphyrins. A crystallographic comparison of 5,10-diphenylporphyrin with the regioisomeric 5,15-disubstituted system reveals striking differences in their conformation. In the free base porphyrins the former uses mainly out-of-plane distortion to alleviate steric strain while in-plane core elongation predominates in the latter. In contrast, the structure of the Cu(II) complex is planar and forms strong p-p aggregates with very small lateral shifts. Macroscopically, the packing is similar to that of porphyrin sponges of the 5,10,15,20-tetraphenylporphyrin type.},
  language  = {en}
}
@article{SengeRyppaFazekasetal.2011,
  author    = {Senge, Mathias O. and Ryppa, Claudia and Fazekas, Marijana and Zawadzka, Monika and Dahms, Katja},
  title     = {5,10-A2B2-Type meso-Substituted PorphyrinsuA Unique Class of Porphyrins with a Realigned Dipole Moment},
  series = {Chemistry - a European journal},
  volume    = {17},
  journal   = {Chemistry - a European journal},
  number    = {48},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0947-6539},
  doi       = {10.1002/chem.201101934},
  pages     = {13562 -- 13573},
  year      = {2011},
  abstract  = {Current applications in porphyrin chemistry require the use of unsymmetrically substituted porphyrins. Many current industrial interests in optics and biomedicine require systems with either pushpull (electron-donating and -withdrawing groups) or amphiphilic systems (hydrophobic and hydrophilic groups). In this context we present the class of 5,10-A2B2-type porphyrins for which two different substituents are positioned in diagonally opposite meso positions. Thus, the intramolecular dipole moment in these tetrapyrroles is positioned along a beta-beta vector passing through two pyrrole rings. This is opposite to the situation of the frequently used 5,15-A2BC porphyrins for which the dipole moment is oriented along a mesomeso axis. We have elaborated syntheses of the 5,10-A2B2 porphyrins by using transition-metal-catalyzed transformations of 5,10-A2 porphyrins or direct substitutions reactions thereof; this gives the target molecules in 2277\% overall yields. The compounds exhibit interesting structural, spectroscopic, and optical features and can serve as building blocks for new porphyrin arrays and applications.},
  language  = {en}
}