Structural effects on sigmatropic shifts in heteroaromatic allyl ethers†
نویسندگان
چکیده
In contrast to the known thermal, exclusively [3,3], Oto Nrearrangement of allyl groups in phenyltetrazoles (1, Scheme 1), the comparable migration of the allyl group in pseudosaccharyl ethers (3; Scheme 2) has been shown to proceed through both [1,3]and [3,3]-mechanisms, 4, 5; for the pseudosaccharyl derivative of the natural product myrtenol (6; Scheme 3) only the product 7 of a [1,3]-shift has been observed; crystallographic data and theoretical calculations provide an explanation of this ease of [1,3]-isomerization and the observed selectivity as being due to conformational constraints and electronic factors.
منابع مشابه
Synthesis of alkynyl ethers and low-temperature sigmatropic rearrangement of allyl and benzyl alkynyl ethers.
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