Koser试剂
羟基（甲苯磺酰氧基）碘苯（HTIB）
HTIB是商业上可获得的用于一系列有机底物的苯基碘化和氧化合成的试剂。例如，酮类产生α-甲苯磺酰氧基酮，而烯烃通过顺式加成形成1,2-二羟基氧基烷烃。
最近报道的方法可以方便地访问Koser的试剂和衍生物：
EA Merritt，VMT Carneiro，LF Silva Jr.，B。Olofsson，J.Org。化学。，2010， 75，7416-7419.54。
Recent Literature
Various α-tosyloxyketones were efficiently prepared in high yields from the reaction of ketones with m-chloroperbenzoic acid and p-toluenesulfonic acid in the presence of a catalytic amount of iodobenzene.
Y. Yamamoto, H. Togo, Synlett, 2006, 798-800.
Various ketones could be reacted into α-tosyloxy ketones in the presence of MCPBA, PTSA•H2O, catalytic amounts of iodine and tert-butylbenzene in a mixture of acetonitrile and 2,2,2-trifluoroethanol. In the reaction, 4-tert-butyl-1-iodobenzene is formed at first and then converted into the α-tosyloxylation reagent 4-tert-butyl-1-[(hydroxy)(tosyloxy)iodo]benzene by the reaction with MCPBA and PTSA•H2O.
A. Tanaka, K. Moriyama, H. Togo, Synlett, 2011, 1853-1854.
Enol esters were rapidly converted in high yields to their corresponding α-tosyloxy ketones in the presence of [hydroxy(tosyloxy)iodo]benzene (HTIB). Aromatic, aliphatic, and cyclic enol esters were found to be suitable substrates for the reaction.
B. Basdevant, C. Y. Legault, J. Org. Chem., 2015, 80, 6897-6902.
HTIB mediates an oxidative transposition of vinyl halides to provide α-halo ketones as useful and polyvalent synthetic precursors. Insights into the mechanism and an enantioselective transformation are reported too.
A. Jobin-Des Lauriers, C. Y. Legault, Org. Lett., 2016, 18, 108-111.
Dehydrosulfurization using a hypervalent iodine(III) reagent enables a simple and efficient preparation of symmetrical and unsymmetrical carbodiimides from the corresponding thioureas. The oxidation afforded carbodiimides in excellent yields and high selectivity. A possible mechanism for the transformation is proposed.
C. Zhu, D. Xu, Y. Wei, Synthesis, 2011, 711-714.
Poly{[4-(hydroxy)(tosyloxy)iodo]styrene} was efficient in the halotosyloxylation reaction of alkynes with iodine or NBS or NCS. The polymer reagent could be regenerated and reused.
J.-M. Chen, X. Huang, Synthesis, 2004, 1557-1558.