Organic Letters
Letter
be obtained free of charge from The Cambridge Crystallographic Data
(17) Roush, W. R.; Spada, A. P. Tetrahedron Lett. 1983, 24, 3693−
3696.
(18) Resubmission of isolated sulfide 25 to the reaction conditions
(DHPB 1, i-Pr2NEt, MeCN, Δ) returned only starting material.
(19) 3-Phenyl substituted pyrone 27 was isolated along with the
dihydropyrone 28, presumably resulting from thiophenol-mediated
desulfurization of the phenyl analogue of sulfide 25 and tautomeriza-
tion. See the Supporting Information for details.
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(15) (Phenylsulfinyl)-, 2-methoxy-, and 2-benzyloxyacetic acid were
also tested, but all gave intractable mixtures of products.
(16) See the Supporting Information. CCDC 974564 (25) contains
the supplementary crystallographic data for this paper. These data can
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