Chemical Science
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Notes and references
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Scheme 5 Formal alkene hydromethylation. Homologation: 14a–k
(0.05–0.2 mmol, 1.0 equiv.), CH2Br2 (2.0–3.0 equiv.), n-butyllithium
(1.5–2.0 equiv.) in THF or Et2O: protodeboronation: 15a–k (0.05–
0.2 mmol, 1.0 equiv., used as crude from homologation step), PhLi (1.1
equiv.), Et2O (0.5–2.0 mL), thiophenol (1.1 equiv.), PC1 (2.5 mol%) in
MeOH/acetone (1 : 1, 0.5–2.0 mL). Yield corresponds to the two-step
homologation-protodeboronation sequence. For the hydroboration
step, we refer to the ESI.† aDerived from O-Ts-protected phenol, O–S
cleavage during reaction.
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Conflicts of interest
The authors declare no conict of interest.
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Acknowledgements
We thank the European Research Council (ERC Advanced Grant
agreement no. 692640) for nancial support.
Chem. Sci.
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