Scheme 8 Proposed reaction mechanism.
Stability of N-Ts-iodoaziridines: Rearrangement. On the other hand, working with two equivalents of indole 1p, at 0. In this latter case, a reaction intermediate analogous to II, Scheme 8 , evolves by intramolecular amination reaction and regeneration of the catalyst. Prepared according to the General Procedure 2 described above, starting from cyclohexanecarboxaldehyde 1. N-[1- 2-Chlorophenyl -2,2-diiodoeth-yl]methylbenzenesulfonamide 3h.
Yamaguchi, N. As reported in the literature and confirmed by our experiments see Table 2 , boron trifluoride is able to almost regioselectively address the nucleophilic attack at the more hindered carbon atom of the aziridine ring. Purification by flash chromatography on deactivated basic alumina activity IV or activity V afforded the cis-iodoaziridine. Pandey, A. Following the observations made during the stability studies to silica above, we were keen to establish whether iodoaziridine 4b could be converted directly to the iodo-aldehyde, which was observed on stirring crude 4b with silica. Chen, C.
Analytical thin-layer chromatography TLC was performed on precoated, glass-backed silica gel plates. Jat, J. Kosaka, S.
Ester substrates bearing a nucleophilic carbonyl give products of an olefin aminohydroxylation. N-[1- 2-Chlorophenyl -2,2-diiodoeth-yl]methylbenzenesulfonamide 3h. Xue, M.
Scheme 8 Proposed reaction mechanism. Synthesis of Diiodide 3h. Ti OEt 4 2.
The crude imine was then recrystallized EtOAc to afford imine 1i as white crystals 6. Similar rearrangements have been highlighted by Yudin converting a-bromoaziridines to a-bromohydrazones.
Li, Synthesis, , The relevant aldehyde However, the stability of the iodoaziridine was greatly enhanced using deactivated basic alumina activity IV vs activity I , with only a small drop in the recovery observed. Forslund, M. Method C.
Yamaguchi, N. The aqueous solution was extracted with CH2Cl2 3 X 30 mL and the combined organic layers were dried Na2SO4 , and the solvent was removed under reduced pressure.
Li, Synthesis, , Prepared according to General Procedure 1 described above, starting from 4-tert-butylbenzaldehyde 1. Rearrangement products of electron-rich aryl iodoaziridines were also discovered, and the formation of an enantioriched N-sulfinyl iodoaziridine was achieved for the first time. The crude cis-iodoaziridine was dissolved in CH2Cl2 16 mL and c. The selectivity is discussed.