De l'action d'aldéhydes sur le chlorure de benzylmagnésium et quelques homologues
作者:A. Jacot-Guillarmod
DOI:10.1002/hlca.19570400611
日期:——
Les homologues du chlorure de benzylmagnésium substitués sur le noyau par un ou plusieurs groupes méthyles en2, 3, 4, 2–4 ou 2–5 donnent avec le butanal, en plus de l'alcool secondaire, un produit de réaction anormale, à savoir un diol. Celui-ci est formé par condensation en ortho, relativement au groupe CH2 MgX, d'une deuxième molécule d'aldéhyde. La proportion de ce produit anormal varie suivant
Isolation and total synthesis of two novel metabolites from the fissurellid mollusc Scutus antipodes
作者:Satish Chand、Peter Karuso
DOI:10.1016/j.tetlet.2017.01.096
日期:2017.3
compounds, scutinin A [d-sorbityl hexakis(p-hydroxybenzoate)] and scutinin B [2-ethylhexane-1,3-bis(p-hydroxybenzoate)] that were identified by spectroscopic analysis and their structures confirmed by totalsynthesis. The compounds were found to have antimicrobial activity but no fish antifeedant activity.
Aliphatic aldehydes undergo a catalytic trimerization to give 1,3-diol monoesters upon treatment with Fe3(CO)12 in pyridine or with Fe3(CO)12-pyridine N-oxide in benzene. Polynuclear carbonylferrates serve as catalyst for this transformation.
commonly known nucleophile, is identified as the catalytic active species. This zwitterion favors nucleophiliccharacter in solution, whereas once confined within the framework, it becomes an electrophile yielding Aldol-Tishchenko selectivity. Computational investigations reveal a structural change in the phosphonium moiety induced by the steric confinement of the framework that makes it accessible and an
a new class of Tishchenko precatalysts and, to a limited extent, precatalysts for the hydroamination/cyclization of aminoalkynes. It is shown that 1 is the most active catalyst for the Tishchenkoreaction. This contribution presents investigations on the scope of the reaction, substrate selectivity, lanthanide-ion size-effect, and kinetic/mechanistic aspects of the Tishchenkoreaction catalyzed by 1