Month: September 2015

Symmetry-controlled rearrangements in Piedfort Units (PU) of 2,4,6-triaryloxy-1,3,5-triazines

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Petra Bombicz, Nikoletta B. Báthori, Alajos Kálmán Struct. Chem., 26, 1611-1619, 2015   Abstract 2,4,6-triaryloxy-1,3,5-triazines (POT) form in general molecular diads, termed as Piedfort Units (PU), in their crystals and their clathrates. Their bulky phenyl substituents (R = Me, F, Cl, Br, I, CN) in ortho, meta or para position substantially hinder internal rotations. Instead, non-crystallographic rotations (ncr) or translations (nct) are the bridges between the semirigid homologues or analogues, occasionally polymorphs. They occur in the space groups R3c (161), Read More …

Strain-Driven Direct Cross-Aldol and -Ketol Reactions of Four-Membered Heterocyclic Ketones

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 Zoltán Dobi, Tamás Holczbauer, and Tibor Soós* Org. Lett., 2015, 17 (11), pp 2634–2637 Abstract Owing to the ring strain and α-heteroatom effect, the four-membered heterocyclic ketones can undergo direct cross-aldol and -ketol reactions without the need for preformed enol or “enolate-like” intermediates. Besides the organocatalyzed cross-ketol addition onto their highly active carbonyl group, their ability to act as a nucleophilic donor has also been explored. As a result, a number of discrete aldol adducts were synthesized and the distinct reactivities were successfully combined into Read More …