Synthesis of 2-aryltryptamines with palladium catalyzed cross-coupling of 2-bromotryptamines and arylboronic acids

Tetrahedron Letters

Volumn 38, Issue 22, 1997, Pages 3871-3874

  Chu, Lin ^a   Fisher, Michael H ^a   Goulet, Mark T ^a   Wyvratt, Matthew J ^a  

^a MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

2 BROMOTRYPTAMINE DERIVATIVE; ARYLBORONIC ACID; BORON; PALLADIUM; TRYPTAMINE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; CHEMICAL REACTION; CHEMICAL STRUCTURE; SYNTHESIS;

EID: 0030905213     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)00797-1     Document Type: Article

References (23)

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10. 1 = H), only the intermediate 9 was formed. Prolonged heating for 1 - 2 days was essential in order to drive the reaction to completion. formula represented
11. b) One equivalent of triethylamine was added in the reaction when a hydrochloride salt of the starting tryptamine(2) was used.
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16. 2O, 2.5 equiv.), LiCl (anhydrous, 3 equiv.), and tetrakis(triphenylphosphine) palladium (purchased from Aldrich, 5 mol %) were added sequentially. The resulting heterogeneous system was then brought up to refluxing condition for 3 - 5 hours under a nitrogen atmosphere. The end point of the reaction was usually accompanied by a change in color of the reaction mixture from yellow to dark orange/brown. When the completion of reaction was confirmed by TLC, the reaction mixture was concentrated directly in vacuo and azeotroped 2 - 3 times with toluene. The organics were dissolved in a mixture of hexane/methylene chloride/ethyl acetate, and flash chromatographed on silica with appropriate mixtures of hexane/ethyl acetate.
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