Hydroxylamine → 6-(4-Chlorobenzenesulfinyl)-hexa-2,4-dienoic acid hydroxyamide

Temperature

0 °C

To a solution of the 6-(4-chlorobenzenesulfinyl)-hexa-2,4-dienoic acid methyl ester (0.80 g, 2.79 mmol) in distilled THF (15 mL) containing an aqueous solution of hydroxylamine (50%/o, 1.7 ml, 25.8 mmol) was added at 0° C. a solution of potassium hydroxide in methanol (1M, 4.5 ml, 4.5 mmol) over a period of 30 minutes. After stirring at 0° C. for 1 hour, distilled water (15 mL) was added and the mixture was made neutral by dropwise addition of concentrated hydrochloric acid (10 M) at 0° C. The aqueous solution was extracted with ethyl acetate (3×50 mL) and the combined extracts were dried over anhydrous MgSO4, and evaporated to dryness. The residue was recrystallised from acetone to give the title compound (0.45 g, 56%) as a pale brown powder, mp 159° C. (decomp).

1. distillationdistilled water (15 mL)
2. additionwas added
3. additionthe mixture was made neutral by dropwise addition of concentrated hydrochloric acid (10 M) at 0° C
4. extractionThe aqueous solution was extracted with ethyl acetate (3×50 mL)
5. dry with materialthe combined extracts were dried over anhydrous MgSO4
6. customevaporated to dryness
7. customThe residue was recrystallised from acetone

ORD record

ord-7bb6139ece9f42889a1d2139b9700e95

Source dataset

uspto-grants-2010_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07683185B2