Diethyl Ether → 10-[(tert-Butyldimethylsilyl)oxy]-3-(trimethylacetoxy)-7,8,9,10-tetrahydrophenanthridine

HRID 1197708Notes

Reaction equation

HRID 1197708 reaction equation
[Si:1]([O:8][CH:9]1[C:22]2[C:13](=[CH:14][N:15]=[C:16]3[C:21]=2[CH:20]=[CH:19][C:18]([OH:23])=[CH:17]3)[CH2:12][CH2:11][CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[H-].[Na+].[CH3:26][C:27]([CH3:37])([CH3:36])[C:28](N1CCSC1=S)=[O:29].C(OCC)C>C1COCC1.C1C=CC=CC=1>[Si:1]([O:8][CH:9]1[C:22]2[C:13](=[CH:14][N:15]=[C:16]3[C:21]=2[CH:20]=[CH:19][C:18]([O:23][C:28](=[O:29])[C:27]([CH3:37])([CH3:36])[CH3:26])=[CH:17]3)[CH2:12][CH2:11][CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]

Participants

7

Reactant 4

HCID 3283Diethyl EtherHCID 24758Sodium hydrideHCID 117695952,2-Dimethyl-1-(2-thioxothiazolidin-3-yl)propan-1-oneHCID 13576196710-[(tert-Butyldimethylsilyl)oxy]-3-hydroxy-7,8,9,10-tetrahydrophenanthridine

Product 1

HCID 1181173110-[(tert-Butyldimethylsilyl)oxy]-3-(trimethylacetoxy)-7,8,9,10-tetrahydrophenanthridineYield 99.1%

Reagents, catalysts & solvents 2

HCID 241BenzeneSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

To a suspension of Compound 141a (1.28 g, 3.88 mmol) in dry THF (50 mL) cooled in an ice-water bath was added NaH (60 percent, 163 mg, 4.08 mmol) followed by stirring for 10 minutes. A yellow-colored solution of Compound 226 (0.789 g, 3.88 mmol) in dry THF (10 mL) was added, and the mixture was then stirred at 25° C. for five minutes. The reaction mixture was quenched with water, extracted with ethyl acetate (50 mL), washed with brine, dried over anhydrous Na2SO4, and evaporated in vacuo to give a residue. Flash column chromatography of the residue (silica gel, 20 percent ethyl ether in benzene) provided Compound 142a (1.59 g, 99 percent): white powder; mp 125°-126.5° C.; Rf =0.49 (silica, 20 percent ethyl ether in benzene); IR (CHCl3) νmax 2957, 2934, 1750, 1261, 1131, 1116, 1027 cm-1 ; 1H NMR (300 MHz, CDCl3) δ8.58 (s, 1 H, H6), 7.98 (d, J=9.1 Hz, 1 H, H1), 7.67 (d, J=2.1 Hz, 1 H, H4), 7.21 (dd, J=9.1 2.1 Hz, 1 H, H2), 5.33 (t, J=2.9 Hz, 1 H, H10), 2.90 (br dd, J=17.2, 3.3 Hz, 1 H, H7), 2.72 (ddd, J=17.2, 11.2, 5.7 Hz, 1 H, H7), 2.17-1.96 (m, 2 H, H8 or H9), 1.83-1.67 (m, 2 H, H8 or H9), 1.31 (s, 9 H, COC(CH3)3), 0.74 (s, 9 H, SiC(CH3)3), 0.12 (s, 6 H, Si(CH3)2); MS (FAB+) m/e (rel intensity) 414 (M+H, 100), 357 (9), 330 (12), 283 (5), 198 (10); HRMS for C24H36NO3Si (M+H), calcd 414.2464, found 414.2484. Anal. Calcd for C24H35NO3Si: C, 69.69; H, 8.53; N, 3.39. Found: C, 69.68; H, 8.44; N, 3.23.

Workup

  1. temperaturecooled in an ice-water bath
  2. stirringthe mixture was then stirred at 25° C. for five minutes
  3. customThe reaction mixture was quenched with water
  4. extractionextracted with ethyl acetate (50 mL)
  5. washwashed with brine
  6. dry with materialdried over anhydrous Na2SO4
  7. customevaporated in vacuo
  8. customto give a residue

Sources & evidence

ORD record
ord-bccce03df94b481d99b09ad01f080aa4
Source dataset
uspto-grants-1994_01
Patent number
US05276159

Reaction notes

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