35365-19-6Relevant articles and documents
Conformational analysis of 2-halocyclohexanones: An NMR, theoretical and solvation study
Yoshinaga, Fabiana,Tormena, Claudio F.,Freitas, Matheus P.,Rittner, Roberto,Abraham, Raymond J.
, p. 1494 - 1498 (2002)
The conformational equilibria of 2-fluoro-, 2-chloro- and 2-iodo-cyclohexanone have been determined in various solvents by measurement of the J2-3 couplings. The observed couplings were analysed using theoretical and solvation calculations to give both the conformer energies in the solvents studied plus the vapour phase energies and the coupling constants in the distinct conformers. These plus previous results for the 2-bromo compound give the conformer energies and couplings of all the 2-halocyclohexanones. In the 2-fluoro compound the axial conformation is the most stable one in the vapour phase (Eeq - Eax = 0.45 kcal mol-1), while the equatorial conformer predominates in all the solvents studied. The other haloketones show similar behaviour, but the energy difference in the vapour phase is larger (Eeq - Eax = 1.05, 1.50 and 1.90 kcal mol-1, for the chloro, bromo and iodo compounds respectively) and the axial conformer is still the prevailing conformer in CCl4 solution for the chloro and bromo ketones and is the major form in all solvents for the iodo compound. The vapour state conformer energies for the fluoro and chloro compounds are in complete agreement with the ab initio calculated energies, but those for the bromo and iodo are not in such good agreement. Both the ab initio calculations and molecular mechanics are used to discuss the origins of the conformer energies. It is shown that the interaction between the C2 halogen and the C=O oxygen in the equatorial conformer is strongly attractive for fluorine, much less so for chlorine, ca. zero for bromine and repulsive for iodine. Comparison of the conformer couplings obtained here with calculated values show generally good agreement.
IBX works efficiently under solvent free conditions in ball milling
Achar, Tapas Kumar,Maiti, Saikat,Mal, Prasenjit
, p. 12834 - 12839 (2014/04/03)
IBX (2-iodoxybenzoic acid), discovered in 1893, is an oxidant in synthetic chemistry whose extensive use is impeded by its explosiveness at high temperature and poor solubility in common organic solvents except DMSO. Since the discovery of Dess-Martin Periodinane in 1983, several modified IBX systems have been reported. However, under ball milling conditions, IBX works efficiently with various organic functionalities at ambient temperature under solvent free conditions. Also, the waste IBA (2-iodosobenzoic acid) produced from the reactions was in situ oxidized to IBX in the following step using oxone and thus reused for multiple cycles by conserving its efficiency (only ～6% loss after 15 cycles). This work describes an overview of a highly economical synthetic methodology which overcomes the problems of using IBX, efficiently in gram scale and in a non-explosive way. This journal is the Partner Organisations 2014.
Enzymatic resolution of stereoisomers of 2-iodocyclohexanol
Kolodiazhna,Kolodiazhna,Kolodiazhnyi
, p. 2175 - 2177 (2013/10/01)
All four optically active stereoisomers of 2-iodocyclohexanol were synthesized. Their enantiomeric purity was determined upon derivatization with Mosher's acid, absolute configuration have been established by chemical correlation.
Stereoselective synthesis of cis-2,5-disubstituted THFs: Application to adjacent bis-THF cores of annonaceous acetogenins
Fujioka, Hiromichi,Maehata, Ryota,Wakamatsu, Shintaro,Nakahara, Kenji,Hayashi, Tatsuya,Oki, Tomohiro
supporting information; experimental part, p. 1054 - 1057 (2012/04/10)
The iodocyclization of γ,δ-unsaturated alcohols in the presence of a silyl enol ether produced cis-2,5-disubstituted tetrahydrofurans in one pot via siloxy intermediates. N-Iodosuccinimide (NIS) effectively worked as an activator of the double bonds in th
