Please explain the easiest preparation methods for PhI=NTs (Isotopic labelled (N15) [N-(p-Toluenesulfonyl)imino]phenyliodinane. Thanks in Advances!
Chapter e-EROS Encyclopedia of Reagents for Organic Synthesis
and use of Ts15NH2
Pardeep
Toluenesulfonyl)imino)phenyliodinane 1: The procedure described by Yamada et al. was followed. Diacetoxyiodobenzene (3.2 g, 10 mmol) was added to a solution of KOH (1.4 g, 25 mmol) and p-toluenesulfonamide (1.7 g, 10 mmol) in methanol (40 mL) at 8 °C. A yellow color developed within 1 min. The cooling bath was removed, and the solution was allowed to warm to room temperature as it was stirred for 3 h. Water (45 mL) was added, and the solution was refrigerated overnight at 0 °C. The precipitate was collected by filtration and air dried to yield 2.9 g of a light-yellow powder. Iodometry indicated 56% purity. The powder was dissolved in methanol (60 mL), a small residue was removed by filtration, and water (60 mL) was added. This solution was refrigerated at -20°C overnight. Filtration and air drying of the precipitate afforded the target molecule 1 as a finely divided yellow powder (2.0 g, 52% yield). This material extensively decomposed over the range 90-120°C. Iodometry indicated this material to be 99.3% pure as CI3H12IN02S. Anal. (C13HI2INO2S) C, H, N. Reduction of the powder with excess aqueous sodium bisulfite afforded 1 mol of iodobenzene and 1 mol of p-toluenesulfonamide per mol of 1 as the only products, as determined by gas chromatography on column A. Infrared spectrum: 3067 (w), 1593 (w), 1571 (w), 1468 (w), 1436 (w), 1232 (m), 1209 (s), 1123 (s), 1087 (s), 933 (s), 81 1 (m), 728 (w), and 651 (m) cm-l. NMR spectrum (in CD30D): 2.45 (singlet, 2.6 H), 7.2-8.4 ppm (11 line multiplet, largest peak at 7.78 ppm, 9.0 H). UV-vis spectrum: (in MeOH) lmax 222 (e 109000 M-I cm-I), 400 (end absorption, B 0.97 M-1 cm-1; in 25% H20-75% MeOH) lmax 225 (e = 89000 M-I cm-I), 400 nm (end absorption, e 1.5 M-1 cm-1]).
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