P-Toluenesulfonamide → Tosylchloramide

To a stirred solution of (DHQ)2 -PHAL (0.11 g, 0.14 mmol, 5 mol %) in 20 mL of acetonitrile and 20 mL of water, in any convenient-sized glass vessel or vial, was added desired acrylate or methacrylates entries 1-10 (all commercially available from Aldrich, FIG. 16 and FIG. 17, 2.8 mmol), Chloramine-T trihydrate (2.42 g, 8.4 mmol, 3 eq) and K2OsO2 (OH)4 (41.6 mg, 0.112 mmol, 4 mol %). As the reaction proceeded to completion over the course of about one and half hours at room temperature, the color of the solution changed from yellow to pale green, then deep green and finally back to yellow. After addition of aqueous sodium sulfite (1.0 g in 15 mL H2O), the phases were separated, and the aqueous phase extracted with ethyl acetate (3×15 mL). The combined organic extracts were washed with brine, dried over MgSO4 and the solvent concentrated to give the crude product, which also contains the p-toluenesulfonamide by-product produced upon the reduction of the excess Chloramine-T. Purification provides compounds as shown in FIG. 16, entries 1-10 with the indicated yields and conditions. NOTE: Replacement of the 3 eq of Chloramine-T with 1.5 eq of Chloramine-T and 1.5 eq of Et4NOAc gives comparable results and reduces the amount of p-toluenesulfonamide by-product formed. This can greatly simplify product isolation, especially in cases where the product and the toluenesulfonamide have similar chromatographic mobilities. ##STR17##

1. customproceeded to completion over the course of about one and half hours at room temperature
2. customthe phases were separated
3. extractionthe aqueous phase extracted with ethyl acetate (3×15 mL)
4. washThe combined organic extracts were washed with brine
5. dry with materialdried over MgSO4
6. concentrationthe solvent concentrated
7. customto give the crude product, which

ORD 기록

ord-064ba804b8c14917ab721826a3e2fe6b

출처 데이터셋

uspto-grants-1999_01

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US05859281