@article{WessigKrebs2021,
  author    = {Wessig, Pablo and Krebs, Saskia},
  title     = {N-aroylsulfonamide-photofragmentation (ASAP)},
  series = {European journal of organic chemistry},
  volume    = {2021},
  journal   = {European journal of organic chemistry},
  number    = {46},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1434-193X},
  doi       = {10.1002/ejoc.202100955},
  pages     = {6367 -- 6374},
  year      = {2021},
  abstract  = {The photochemical fragmentation of N-aroylsulfonamides 9 (ASAP) is a powerful method for the preparation of various biaryls. Compounds 9 are easily accessible in two steps from amines by treatment with arenesulfonyl chlorides and aroyl chlorides. Many of these compounds were prepared for the first time. The irradiation takes place in a previously developed continuous-flow reactor using inexpensive UVB or UVC fluorescent lamps. Isocyanates and sulphur dioxide are formed as the only by-products. The ASAP tolerates a variety of functional groups and is even suited for the preparation of phenylnaphthalenes and terphenyls. The ASAP mechanism was elucidated by interaction of photophysical and quantum chemical (DFT) methods and revealed a spirocyclic biradical as key intermediate.},
  language  = {en}
}
@article{VijayakrishnanIssareeCoriloetal.2011,
  author    = {Vijayakrishnan, Balakumar and Issaree, Arisara and Corilo, Yuri E. and Ferreira, Christina Ramires and Eberlin, Marcos N. and Peter, Martin G.},
  title     = {MSn of the six isomers of (GlcN)(2)(GlcNAc)(2) aminoglucan tetrasaccharides (diacetylchitotetraoses) rules of fragmentation for the sodiated molecules and application to sequence analysis of hetero-chitooligosaccharides},
  series = {Carbohydrate polymers : an international journal devoted to scientific and technological aspects of industrially important polysaccharides},
  volume    = {84},
  journal   = {Carbohydrate polymers : an international journal devoted to scientific and technological aspects of industrially important polysaccharides},
  number    = {2},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0144-8617},
  doi       = {10.1016/j.carbpol.2010.04.041},
  pages     = {713 -- 726},
  year      = {2011},
  abstract  = {The six possible isomers of di-N-acetylchitotetraoses [AADD, ADDA, ADAD, DADA, DAAD, and DDAA, where D stands for 2-amino-2-deoxy-3-D-glucose (GlcN) and A for 2-acetamido-2-deoxy-beta-D-glucose (GlcNAc)] were analyzed by ESI(+)-MSn. Collision induced dissociation via MSn experiments were performed for the sodiated molecules of m/z 769 [M+Na](+) for each isomer, and fragments were generated mainly by glycosidic bond and cross-ring cleavages. Rules of fragmentation were then established. A reducing end D residue yields the (O.2)A(4) cross-ring [M-59+Na](+) fragment of m/z 710 as the most abundant, whereas isomers containing a reducing end A prefer to lose water to form the [M-18+Na](+) ion of m/z 751, as well as abundant (O.2)A(4) cross-ring [M-101+Na](+) fragments of m/z 668 and B-3 [M-221+Na](+) ions of m/z 548. MS3 of C- and Y-type ions shows analogous fragmentation behaviour that allows identification of the reducing end next-neighbour residue. Due to gas-phase anchimeric assistance, B-type cleavage between the glycosidic oxygen and the anomeric carbon atom is favoured when the glycon is an A residue. Relative ion abundances are generally in the order B >> C > Y, but may vary depending on the next neighbour towards the non-reducing end. These fragmentation rules were used for partial sequence analysis of hetero-chitooligosaccharides of the composition D(2)A(3), D(3)A(3), D(2)A(4), D(4)A(3), and D(3)A(4).},
  language  = {en}
}