Regioselective Mukaiyama hydroperoxysilylation of 2-alkyl- or 2-aryl-prop-2-en-1-ols: application to a new synthesis of 1,2,4-trioxanes

Mn-, Fe-, and Co-Catalyzed Radical Hydrofunctionalizations of Olefins

“…A wide variety of cyclic peroxides such as 1,2-dioxanes, 120,127,128,129,130 1,2-dioxolanes, 118,119,120,121,129,130,131,132 and 1,2,4-trioxanes, 117,133,134,135,136,137,138,139,140,141 may be obtained using the Mukaiyama/Isayama 103,104 method on particular substrates. These have been reviewed elsewhere.…”

Synthesis of “Trioxaquantel”® Derivatives as Potential New Antischistosomal Drugs

“…[36] In our case, the strategy for the preparation of the trioxane 9 (Scheme 3, b) was based on the highly regioselective Markovnikov reaction of 2-methylprop-2-en-1-ol under Mukaiyama's and Isayama's conditions to prepare the silyl peroxide 8. [37,38] This reaction was sensitive to the nature of the catalyst [39] and to the solvent: in dichloroethane, silylperoxidation is 6 to 8 times slower than in alcohol. [36] Agitation was also very important: the more vigorous the agitation, the more oxygen is dissolved and the better is the yield.…”

“…The solution was concentrated and dried under vacuum. A brownish oil corresponding to compound 5 was obtained (37 75 (m, 1 H, HC17Ј), 3.66-3.52 (m, 1 H, HC3), 3.62-3.52 (m, 1 H, HC1), 3.24-3.09 (m, 1 H, HC3) 14 (m, 1 H, HC8Ј), 2.17-2.05 (m, 1 H, HC8Ј), 1.87 (m, 2 H, HC15Ј, HC19Ј), 1.85-1.80 (m, 2 H, HC16Ј, HC18Ј), 1.70-1.51 (m, 2 H, HC16Ј, HC18Ј), 1.64-1.51 (m, 2 H, HC15Ј, HC19Ј), 1.72-1.49 (m, 1 H, HC9Ј), 1.07-1.00 (m, 6 H, H 3 C13Ј, H 3 C14Ј), 1.00-0.91 (m, 3 H, H 3 C11Ј) ppm. 13 were dissolved under argon in CH 2 Cl 2 (2 mL).…”

Synthesis of Cyclic Peroxides

“…Thiol olefin co-oxygenations of 3-unsubstituted allyl alcohols 575 (TOCO reaction, see also Schemes 51-54, Section II.A.5) afford the corresponding hydroperoxyalcohol intermediates 576, which are condensed in the same vessel with ketones to give the corresponding trioxanes 577 in moderate to high yield (Scheme 163a) 487 . Likewise, Co(acac)-catalyzed Mukaiyama hydroperoxysilylation of allyl alcohols 575 efficiently produce triethylsilyl substituted β-hydroperoxyalcohols 578 (60%), which are condensed with aldehydes and ketones to give the corresponding trioxanes 579 (40-90%) (Scheme 163b) 488 . Spiro-1,2,4-trioxanes were obtained by the same method using bis(2,2,6,6-tetramethyl-3,5-heptanedionato)cobalt(II) as mediator 489 .…”