meta-Selective Aromatic Borylation as Key Step in the Synthesis of Poipuol

Abstract

A synthesis of the marine natural product poipuol is reported. The key reaction sequence consists of an iridium-catalyzed meta-selective CH-borylation followed by the conversion of the resulting arylboronic ester into an aryl chloride.

Key words

meta-selective aromatic substitution - boron - iridium - natural products - total synthesis

References

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7

The crystal data of compound 11 have been deposited at the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC 686558. Crystal data: C₂₁H₃₁BCl₂O₄, M = 429.17, monoclinic, C2/c, a = 16.8261 (9) Å, b = 13.2384 (7) Å, c = 21.5067 (13) Å, β = 104.026 (4)˚, V = 4647.8 (4) Å^³, Z = 8, D _calcd = 1.227 g/cm^³, 20619 collected reflections, 4102 independent (R _int = 0.0775), R1 = 0.0339, wR2 = 0.0709 (all data).