@article{PihlajaSinkkonenStajeretal.2011,
  author    = {Pihlaja, Kalevi and Sinkkonen, Jari and Stajer, Geza and Koch, Andreas and Kleinpeter, Erich},
  title     = {1-Oxo-1,3-dithiolanes - synthesis and stereochemistry},
  series = {Magnetic resonance in chemistry},
  volume    = {49},
  journal   = {Magnetic resonance in chemistry},
  number    = {7},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {0749-1581},
  doi       = {10.1002/mrc.2764},
  pages     = {443 -- 449},
  year      = {2011},
  abstract  = {1-Oxo-1,3-dithiolane (4) and its cis- and trans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO(4) in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with (1)H and (13)C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=O(ax) envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=O(ax) (30 and 27\%) as well as S=O(eq) (21 and 22\%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of (1)H-(1)H coupling constants and (1)H and (13)C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data.},
  language  = {en}
}
@article{ReicheStarkeKleinpeteretal.1999,
  author    = {Reiche, K. B. and Starke, Ines and Kleinpeter, Erich and Holdt, Hans-J{\"u}rgen and Pihlaja, Kalevi and Oksaman, P. and Ovcharenko, V. V.},
  title     = {Fragmentation of imine-type meta-bridged bis(benzo crown ether)s under electron impact},
  year      = {1999},
  language  = {en}
}
@article{StarkeSarodnickOvcharenkoetal.2004,
  author    = {Starke, I. and Sarodnick, Gerhard and Ovcharenko, V. V. and Pihlaja, Kalevi and Kleinpeter, Erich},
  title     = {Quinoxalines : Part 13: Synthesis and mass spectrometric study of aryloxymethylquinoxalines and benzo[b]furylquinoxalines},
  issn      = {0040-4020},
  year      = {2004},
  abstract  = {A series of new aryloxymethylquinoxalines, benzo[b]- and naphtho[2,1-b] fury] quinoxalines, possessing potential biological activity, was prepared, characterized by IR and NMR spectroscopy and their electron ionization (EI) mass spectra studied in detail. The aryloxymethylquinoxalines were obtained by reacting halogenomethylquinoxalines with bifunctional O-nucleophiles. The benzo[b]furylquinoxalines and naphtho[2, I -b]furylquinoxalines were prepared via two routes, which differed in the order of the two cyclization steps involved in the syntheses. The composition of the ions obtained by El mass spectrometry were determined by accurate mass measurements and the fragmentation pathways clarified by B/E linked scans and collision induced dissociation. The mass spectrometric behaviour of the compounds studied as to the possible loss of OH' radicals proved to be very characteristic. (C) 2004 Elsevier Ltd. All rights reserved},
  language  = {en}
}
@article{TahtinenBagnoKochetal.2004,
  author    = {Tahtinen, Petri and Bagno, Alessandro and Koch, Andreas and Pihlaja, Kalevi},
  title     = {Conformational analysis of saturated trans-fused 1,3,2-benzoxazaphosphinine 2-oxides - DFT calculation of NMR J(PH) coupling constants},
  issn      = {1434-193X},
  year      = {2004},
  abstract  = {The (3)J(P,H) and (4)J(P,H) spin-spin coupling constants of a selected test set of organophosphorus compounds, calculated by density functional theory (DFT) methods, were found to correlate well with the experimentally measured coupling constants. The contribution of the spin-dipole (SD) term to the coupling constants was found to be negligible, and the diamagnetic and paramagnetic spin-orbit (DSO and PSO) terms cancelled each other, as in the case of J(H,H). Calculation solely of the Fermi contact (FC) term was found to be sufficient to provide good estimates of the coupling constants. In the second part of the work, the conformational equilibria and coupling constants in 2-bis(2- chloroethyl)amino-trans-octahydro-2H-1,3,2-benzoxazaphosphinine 2-oxide and its 3-methyl derivative were studied. DFT methods failed in predicting the relative stabilities of the conformations but yielded good geometries and coupling constants. Optimization of the conformations at the Moller-Plesset second-order perturbation theory (MP2) level resulted in energy differences compatible with previous experimental observations. ((C) Wiley-VCH Verlag GmbH \& Co. KGaA, 69451 Weinheim, Germany, 2004)},
  language  = {en}
}