Triphenylphosphine → 7-((1,1-Dimethylethoxy)carbonyl)-2-(2-methoxyphenyl)-5,6,7,8-tetrahydro-8-(2-((triphenylmethyl)thio)ethyl)-imidazo[1,2-a]pyrazine

HRID 901124

Reaction equation

HRID 901124 reaction equation
C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.CCOC(/N=N/C(OCC)=O)=O.[C:32]1([C:38]([C:46]2[CH:51]=[CH:50][CH:49]=[CH:48][CH:47]=2)([C:40]2[CH:45]=[CH:44][CH:43]=[CH:42][CH:41]=2)[SH:39])[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=1.[CH3:52][C:53]([CH3:78])([O:55][C:56]([N:58]1[CH2:63][CH2:62][N:61]2[CH:64]=[C:65]([C:67]3[CH:72]=[CH:71][CH:70]=[CH:69][C:68]=3[O:73][CH3:74])[N:66]=[C:60]2[CH:59]1[CH2:75][CH2:76]O)=[O:57])[CH3:54]>C1COCC1>[CH3:54][C:53]([CH3:78])([O:55][C:56]([N:58]1[CH2:63][CH2:62][N:61]2[CH:64]=[C:65]([C:67]3[CH:72]=[CH:71][CH:70]=[CH:69][C:68]=3[O:73][CH3:74])[N:66]=[C:60]2[CH:59]1[CH2:75][CH2:76][S:39][C:38]([C:32]1[CH:33]=[CH:34][CH:35]=[CH:36][CH:37]=1)([C:40]1[CH:41]=[CH:42][CH:43]=[CH:44][CH:45]=1)[C:46]1[CH:47]=[CH:48][CH:49]=[CH:50][CH:51]=1)=[O:57])[CH3:52]

Participants

6

Reactant 4

HCID 11776TriphenylphosphineHCID 77281Benzenemethanethiol, alpha,alpha-diphenyl-HCID 5462977Diethyl azodicarboxylateHCID 220168267-((1,1-Dimethylethoxy)carbonyl)-8-(2-hydroxyethyl)-2-(2-methoxyphenyl)-5,6,7,8-tetrahydro-imidazo[1,2-a]pyrazine

Product 1

HCID 220168347-((1,1-Dimethylethoxy)carbonyl)-2-(2-methoxyphenyl)-5,6,7,8-tetrahydro-8-(2-((triphenylmethyl)thio)ethyl)-imidazo[1,2-a]pyrazineYield 111%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

Triphenylphosphine (4.08 g, 15.5 mmol) was dissolved in THF (25 ml), cooled to about 0° C. under N2 and Diethylazodicarboxylate (2.45 ml, 15.54 mmol) was added at a dropwise rate so that the reaction temperature was maintained at about <3° C. Stirring was continued for about 12 hour at 0° C. A mixture of the triphenylmethanethiol (4.30 g, 15.54 mmol) and the product from Step 13.e. (2.90 g, 7.77 mmol) in THF (25 ml) was added at a dropwise rate. The resulting mixture was stirred for about 1 hour at about 0° C. and then allowed to warm to room temperature. The mixture was concentrated under reduced pressure and the residue dissolved in ether (40 ml) and allowed to stand overnight. The solid was filtered off and the filtrate was concentrated then purified by flash chromatography on silica gel using 4:1/hexanes:EtOAc and then 4:1/hexanes:EtOAc as eluants. The product fractions were combined and concentrated under reduced pressure to obtain a pale yellow foam (5.49 g, 111%) which was used without further purification. Mass spec. 632.4 MH+.

Workup

  1. temperaturewas maintained at about <3° C
  2. stirringThe resulting mixture was stirred for about 1 hour at about 0° C.
  3. temperatureto warm to room temperature
  4. concentrationThe mixture was concentrated under reduced pressure
  5. dissolutionthe residue dissolved in ether (40 ml)
  6. waitto stand overnight
  7. filtrationThe solid was filtered off
  8. concentrationthe filtrate was concentrated
  9. customthen purified by flash chromatography on silica gel using 4:1/hexanes
  10. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-e9d00e75fda44b72bfd23d4f7dd3ef0c
Source dataset
uspto-grants-2008_04
Patent number
US07361656B2

Linked notes

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