Nitrobenzene → 3beta,17beta-Di(trifluoroacetoxy)-9alpha-fluoro-5alpha-androstane

HRID 259219

Reaction equation

HRID 259219 reaction equation
[F:1][C:2]([F:33])([F:32])[C:3]([O:5][C@H:6]1[CH2:23][CH2:22][C@@:21]2([CH3:24])[C@@H:8]([CH2:9][CH2:10][C@@H:11]3[C@@H:20]2[CH2:19][CH2:18][C@@:16]2([CH3:17])[C@H:12]3[CH2:13][CH2:14][C@@H:15]2[O:25][C:26](=[O:31])[C:27]([F:30])([F:29])[F:28])[CH2:7]1)=[O:4].[N+](C1C=CC=CC=1)([O-])=O.[F:43]C(F)(F)C([O-])=O.[Na+].FOC(F)(F)F>FC(Cl)(Cl)Cl>[F:1][C:2]([F:32])([F:33])[C:3]([O:5][C@H:6]1[CH2:23][CH2:22][C@@:21]2([CH3:24])[C@@H:8]([CH2:9][CH2:10][C@@H:11]3[C@:20]2([F:43])[CH2:19][CH2:18][C@@:16]2([CH3:17])[C@H:12]3[CH2:13][CH2:14][C@@H:15]2[O:25][C:26](=[O:31])[C:27]([F:29])([F:30])[F:28])[CH2:7]1)=[O:4]

Participants

6

Reactant 4

HCID 7416NitrobenzeneHCID 78989Hypofluorous acid, trifluoromethyl esterHCID 517019Sodium TrifluoroacetateHCID 867349623beta, 17beta-Di(trifluoroacetoxy)-5alpha-androstane

Product 1

HCID 867349613beta,17beta-Di(trifluoroacetoxy)-9alpha-fluoro-5alpha-androstaneYield 39.4%

Reagents, catalysts & solvents 1

HCID 6389TrichlorofluoromethaneSolvent

Procedure

A well-stirred solution of 3β, 17β-di(trifluoroacetoxy)-5α-androstane (2.5 g, 5.15 mmole, prepared by treatment of 5α-androstane-3β,17β-diol with trifluoroacetic anhydride in pyridine), nitrobenzene (800 mg, 6.5 mmole) and sodium trifluoroacetate (10 g, 73.5 mmole) in fluorotrichloromethane (45 ml) was treated with trifluoromethyl hypofluorite (8.5 mmole) at -20° for 2.5 hours, air being admitted to the reaction vessel during this time. Thereafter the solution was purged with nitrogen and the solvent was removed in vacuo. The residue was dissolved in chloroform and the resulting solution was washed with aqueous sodium bicarbonate and water and was then dried, whereafter the product was chromatographed on silica gel (125 g). Elution with chloroform:hexane (3:7) gave unreacted starting material (308 mg), while subsequent elution with chloroform:hexane (7:13) gave 3β,17β-di(trifluoroacetoxy)-9α-fluoro-5α-androstane (1.02 g), which crystallized from hexane as prisms (917 mg) m.p. 140°-142°; [α] 24D - 22° (c 1.47, CHCl3). (Found C,55.10; H,5.78; F,26.35%;m/e 502. C33H29O4F7 requires C,54.97; H,5.82; F,26.47%; M+ 502).

Workup

  1. customThereafter the solution was purged with nitrogen
  2. customthe solvent was removed in vacuo
  3. dissolutionThe residue was dissolved in chloroform
  4. washthe resulting solution was washed with aqueous sodium bicarbonate and water
  5. customwas then dried, whereafter the product
  6. customwas chromatographed on silica gel (125 g)
  7. washElution with chloroform:hexane (3:7)
  8. customgave unreacted
  9. washwhile subsequent elution with chloroform:hexane (7:13)

Sources & evidence

ORD record
ord-50793cc9a5b34832bb6f4dd45901331d
Source dataset
uspto-grants-1977_07
Patent number
US04036864

Linked notes

Loading…