反应详情

温度

25 °C

(1S,3S,5R,6R) 2,2-Dimethyl-6-phenoxyacetamidopenam-3-carboxylic acid-1-oxide diphenylmethyl ester (55.06 gms, 100.00 mmoles) was dissolved in sieve-dried, peroxide-free dioxane (550 mls) at 25° C. with good agitation. To this solution, in order, were added pyridine (24.21 mls, 23.73 gms, 300.00 mmmoles), acetyl bromide (1.48 mls, 2.46 gms, 20.00 mmoles) and methylsilyl triisocyanate (89% pure, 21.30 mls, 25.34 gms, 133.33 mmoles). The slurry was heated to reflux (ca 100° C.) for 4 hours. The reaction mixture was then cooled to 25° C. and filtered, with the clear yellow filtrate being concentrated in vacuo at 50° C. to a highly viscous oil. The oil was dissolved in hot 2-propanol (~80° C., 3000 mls), filtered, and allowed to cool to 25° C. The slurry was cooled to 0°-5° C. for 2 hours, filtered, and washed with 2-propanol (0°-5° C., 400 mls), and oven-dried at 45° C. to constant weight. Yield: 38.6 gms, 75% of white crystalline title compound. The 80 MHz H' NMR spectrum was clean and consistent for the desired structure.

1. customin sieve-dried
2. customat 25° C.
3. temperatureThe slurry was heated
4. temperatureto reflux (ca 100° C.) for 4 hours
5. filtrationfiltered, with the clear yellow filtrate
6. concentrationbeing concentrated in vacuo at 50° C. to a highly viscous oil
7. dissolutionThe oil was dissolved in hot 2-propanol (~80° C., 3000 mls)
8. filtrationfiltered
9. temperatureto cool to 25° C
10. temperatureThe slurry was cooled to 0°-5° C. for 2 hours
11. filtrationfiltered
12. washwashed with 2-propanol (0°-5° C., 400 mls)
13. customoven-dried at 45° C. to constant weight