AUyl acetates synthesis

A combination of radical and electron transfer steps mediated by manganese triacetate has been used in the synthesis of 5-acetoxyfuranones 21 through carbox-ymethyl radical addition to mono- and disubstituted alkynes 20, followed by oxidative cyclization of the resulting vinyl radicals 22 (Scheme 2.4). The cyclic intermediate 24 is transformed into the furanone 21 through stepwise one-electron oxidation and capture of the resulting aUyl cation 26 by acetate. 

Gnerra, E.M., Mish, M.R., and Carreira, E.M., Versatile, diastereoselective additions of sUyl ketene acetals, aUyl trihntylstannane, and Me3SiCN to N-acyl pyrazolines asymmetric synthesis of densely functionalized pyrazohdines, Org. Lett. 2 (26), 4265, 2000. 

Group transfer polymerization allows the synthesis of block copolymers of different methacrylate or acrylate monomers, such as methyl methacrylate and aUyl methacrylate [Herder, 1996 Webster and Sogah, 1989]. The synthesis of mixed methacrylate acrylate block copolymers requires that the less reactive monomer (methacrylate) be polymerized first. The silyl dialkylketene acetal propagating center from methacrylate polymerization is more reactive for initiation of acrylate polymerization than the silyl monoalkylketene acetal propagating center from acrylate polymerization is for initiation of methacrylate polymerization. Bifunctional initiators such as l,4-bis(methoxytrimethylsiloxymethylene)cyclohexane (XXXin) are useful for synthesizing ABA block copolymers where the middle block is methacrylate [Steinbrecht and Bandermann, 1989 Yu et al., 1988]. 

Cao, Y.L. Zhang, H.Q.J. Homogeneous synthesis and characterization of cellulose acetate butyrate (CAB) in l-aUyl-3- methylimidazolium chloride (AmimCl) ionic liquid. Ind. Eng. Chem. Res. 2004,50 (13), 7808-7814. 

An attractive alternative synthesis was likewise developed by Firmenich. [105, 106] Pentylcyclopentenol, is enzymatically transesterified with dimethyl malo-nate, whereby the (S)-enantiomer remains unaltered, but this can be racemised in the presence of sulfuric acid. The malonate is converted into an allylsilylke-tene acetal, which is then subjected to a Claisen rearrangement this proceeds under the control of the aUyl alcohol at relatively low temperatures and with high stereoselectivity. After decarboxylation, there follows the key step in the synthesis a n-selective epoxidation with highly electrophilic peroxy-acids, such as peroxytrifluoroacetic acid. The high n-selectivity arises from electrostatic effects between the more electron-rich r-side of the douple bond and the partial... 

R. E. Giote, E. R. Jarvo, Org. Lett. 2009, 11, 485 88. PaUadium-catalyzed, one-pot, three-component synthesis of homoaUyhc amines from aldehydes, anisidine, and aUyl trifluoro acetate. 

S) -epichlorohydrin. The authors also found that mild acidic treatment of the open-chain acetal 1212-induced cycHzation to the bicycHc N,0-acetal (—)-1215, which could be aUylated under the same conditions to give mainly the equatorial aUyl intermediate 1216, although not separable from its isomer. However, after a similar cross-metathesis and hydrogenation, the ketone diastereomers could be separated. The major ketone (—)-1217 underwent a spontaneous double cycHzation upon exposure to trifluoroacetic add, thus completing the first reported synthesis of... 

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