Heterogeneous Catalysis: Ni/C-Catalyzed Cross-Couplings en route to Allylated­ Aromatics: Application to a Precursor to Coenzyme Q₁₀

Abstract

The readily available, heterogeneous, and inexpensive catalyst nickel-on-charcoal (Ni/C) can be used to mediate couplings between vinyl alanes and benzylic chlorides under very mild conditions and in good yields. Although such allylated aromatics are themselves important compounds, as demonstrated in this work, their syntheses under the ‘green chemistry’ conditions used can smoothly arrive at precursors to valued quinone natural products, such as the nutraceutical coenzyme Q₁₀.

Key words

heterogeneous catalysis - nickel-on-charcoal - cross-couplings - allylated aromatics - coenzyme Q₁₀

References

• For a related study using Ni(0) under homogeneous conditions, see:
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1

Lipshutz, B. H.; Mollard, P.; Pfeiffer, S. S.; Chrisman, W., submitted.

8

Lipshutz, B. H.; Tasler, S.; Chrisman, W.; Spliethoff, B.; Tesche, B. J. Org. Chem. in press.