Palladium-Catalyzed Sonogashira Coupling of 2,3-Dibromonorbornadiene: Synthesis of Symmetrical and Unsymmetrical Norbornadiene-2,3-diynes

Abstract

Efficient syntheses of symmetrical (2 steps) and unsymmetrical (3 steps) norbornadiene-2,3-diynes 1 and 2 have been developed. Palladium-catalyzed Sonogashira coupling of 2,3-dibromonorbornadiene (8) with alkynes, using catalytic amount of Pd(PPh₃)₄, CuI, Et₃N or BuNH₂ in THF or toluene, provided symmetrical and unsymmetrical norbornadiene-2,3-diynes in good yields.

Key words

palladium - Sonogashira coupling - enediyne - norbornadiene

References

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13

For examples on the study of the effect of solvent in Sonogashira coupling, see Ref. [11c] and references cited therein.

14

See Ref. [11c] and references cited therein.