Pyridine → HCID 13188191, compound

HRID 851337Notes

Reaction equation

HRID 851337 reaction equation
N1C=CC=CC=1.[CH2:7]1[CH2:25][O:24][C:9]2([CH2:15][O:14][C:13]([CH3:23])([CH2:16][CH2:17][CH2:18][CH:19]([CH3:22])[CH2:20][OH:21])[CH2:12][CH2:11][CH2:10]2)[O:8]1>C(Cl)Cl.[O-2].[O-2].[O-2].[Cr+6]>[CH2:25]1[CH2:7][O:8][C:9]2([CH2:15][O:14][C:13]([CH3:23])([CH2:16][CH2:17][CH2:18][CH:19]([CH3:22])[CH:20]=[O:21])[CH2:12][CH2:11][CH2:10]2)[O:24]1

Participants

5

Reactant 2

HCID 1049PyridineHCID 13188190HCID 13188190, compound

Product 1

HCID 13188191HCID 13188191, compoundYield 68.6%

Reagents, catalysts & solvents 2

HCID 10219390chromium (VI) trioxideCatalystHCID 6344DichloromethaneSolvent2×

Conditions

Temperature
-20 °C

Procedure

A solution of pyridine (6.8 g, 0.086 mol) and chromium trioxide (4.3 g, 0.043 mol) in methylene chloride (450 ml) at 23° C. in a nitrogen atmosphere is stirred for 45 minutes. The mixture is cooled to -20° C. and celite (20 g) is added followed by 6,6-ethylenedioxy-2-methyl-2-(4'-methyl-5'-hydroxypentyl)-oxepane (1.95 g, 0.00717 mol) in methylene chloride (50 ml). The mixture is stirred for 1 hour at -20° C. and 30 minutes at 0° C. The mixture is then filtered and the celite cake is washed with methylene chloride (10×50 ml). The filtrate and washings are combined and washed with satd. NaHCO3 (2×150 ml). The methylene chloride phase is separated, dried (MgSO4) and the solvents are removed at reduced pressure. The crude product (1.9 g) is chromatographed on SilicAR CC-7 (50 g) in hexane. Elution with 15% ethyl acetate/hexane gives 6,6-ethylenedioxy-2-methyl-2-(4'-methyl-5'-oxopentyl)-oxepane (19) as a clear colorless oil (1.33 g, 68%): nmr (CDCl3) δ1.10 (d, J=6 Hz, 3H, CH3 --CH--CHO), 3.42 (s, 2H, O--CH2 --C), 3.97 (s, 4H, ketal), 9.53 (d, J=2H, 1H, CH--CHO).

Workup

  1. additioncelite (20 g) is added
  2. filtrationThe mixture is then filtered
  3. washthe celite cake is washed with methylene chloride (10×50 ml)
  4. washwashed with satd
  5. customThe methylene chloride phase is separated
  6. dry with materialdried (MgSO4)
  7. customthe solvents are removed at reduced pressure
  8. customThe crude product (1.9 g) is chromatographed on SilicAR CC-7 (50 g) in hexane
  9. washElution with 15% ethyl acetate/hexane

Sources & evidence

ORD record
ord-11c7b7cb84fd46b8badac47868501efe
Source dataset
uspto-grants-1983_05
Patent number
US04384126

Reaction notes

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