HCID 67495057, compound → HCID 57751210, compound

HRID 658556Notes

Reaction equation

HRID 658556 reaction equation
[C:1]([O:5][C:6]([NH:8][N:9]=[CH:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH2:15]([Si@@]1(Cl)N(C)[C@H](C)C(C2C=CC=CC=2)O1)[CH:16]=[CH2:17]>C(Cl)Cl>[C:1]([O:5][C:6]([NH:8][NH:9][C@H:10]([C:11]([CH3:14])([CH3:13])[CH3:12])[CH2:17][CH:16]=[CH2:15])=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

4

Reactant 2

HCID 67495057HCID 67495057, compoundHCID 86631998HCID 86631998, compound

Product 1

HCID 57751210HCID 57751210, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

N′-(2,2-Dimethyl-propylidene)-hydrazinecarboxylic acid tert-butyl ester (12 g, 59.9 mmoles) was charged to a dried, 3-neck, 1 L round bottom flask with thermometer, magnetic stirrer, and nitrogen atmosphere. Anhydrous methylene chloride (200 mL) was charged to the flask using a catheter. The mixture was chilled to 0° C. with an ice bath. (R,R)-2-Allyl-2-chloro-3,4-dimethyl-5-phenyl-[1,3,2]oxazasilolidine (24.07 g, 89.87 mmoles) was subsequently added to the flask under inert conditions. Within minutes, the originally light yellow solution turned transparent dark yellow. The reaction was stirred for 6 hr at 0° C., then allowed to warm to room temperature, and stirred overnight, while being monitored by TLC. The reaction was quenched by adding ca. 25 mL methanol, resulting in a lightening of color. The solution was concentrated and the residue was diluted with 100 mL of ethyl acetate and 100 mL of water. The phases were separated and the aqueous layer was extracted with ethyl acetate twice. The organic phases were combined, washed with brine, dried over Na2SO4 and concentrated. The resulting oil was purified by column chromatography using 10% ethyl acetate in hexanes. Purified (S)—N′-(1-tert-butyl-but-3-enyl)-hydrazinecarboxylic acid tert-butyl ester was obtained as an oil (2.87 g, 24.4% yield). An impure fraction was also collected (3.17 g). Rf=0.44 (5:1 hexanes:ethyl acetate, 12 visualization); 1H NMR (400 MHz, CDCl3) δ 6.07 (br, 1H, NH), 5.85 (m, 1H), 5.0 (dd, 2H), 2.6 (m, 1H), 2.33 (m, 1H), 2.3 (m, 1H), 1.4 (s, 9H), 0.9 (s, 9H).

Workup

  1. waitWithin minutes
  2. temperatureto warm to room temperature
  3. stirringstirred overnight
  4. customThe reaction was quenched
  5. additionby adding ca. 25 mL methanol
  6. customresulting in a lightening of color
  7. concentrationThe solution was concentrated
  8. additionthe residue was diluted with 100 mL of ethyl acetate and 100 mL of water
  9. customThe phases were separated
  10. extractionthe aqueous layer was extracted with ethyl acetate twice
  11. washwashed with brine
  12. dry with materialdried over Na2SO4
  13. concentrationconcentrated
  14. customThe resulting oil was purified by column chromatography

Sources & evidence

ORD record
ord-f94193c456a64201864770ac514c7c1d
Source dataset
uspto-grants-2011_12
Patent number
US08076517B2

Reaction notes

Loading…