Unlike the Sonogashira coupling, the CastroâStephens coupling can produce heterocyclic compounds when a nucleophilic group is ortho to the aryl halide, although this typically requires use of
dimethylformamide (DMF) as solvent.[7][8]
References
^
abcStephens, R. D.; Castro, C. E. (1963). "The Substitution of Aryl Iodides with Cuprous Acetylides. A Synthesis of Tolanes and Heterocyclics". J. Org. Chem.28 (12): 3313â3315.
doi:
10.1021/jo01047a008.
^von Braun, Julius; Manz, Gottfried (1931). "Fluoranthen und seine Derivate. III. Mitteilung" [Fluoranthene and its derivatives. III. Notification]. Justus Liebigs Ann. Chem. (in German). 488 (1): 111â126.
doi:
10.1002/jlac.19314880107.
^Batu, Gunes; Stevenson, Robert (1980). "Synthesis of natural isocoumarins, artemidin and 3-propylisocoumarin". J. Org. Chem.45 (8): 1532â1534.
doi:
10.1021/jo01296a044.
^Castro, Charles E.; Havlin, R.; Honwad, V. K.; Malte, A. M.; Moje, Steve W. (1969). "Copper(I) Substitutions. Scope and Mechanism of Cuprous Acetylide Substitutions". J. Am. Chem. Soc.91 (23): 6464â6470.
doi:
10.1021/ja01051a049.