29584-22-3Relevant articles and documents
Catalytic synthesis of 9-cis-retinoids: Mechanistic insights
Kahremany, Shirin,Kubas, Adam,Tochtrop, Gregory P.,Palczewski, Krzysztof
supporting information, p. 10581 - 10595 (2019/07/22)
The regioselective Z-isomerization of thermodynamically stable all-trans retinoids remains challenging, and ultimately limits the availability of much needed therapeutics for the treatment of human diseases. We present here a novel, straightforward approach for the catalytic Z-isomerization of retinoids using conventional heat treatment or microwave irradiation. A screen of 20 transition metal-based catalysts identified an optimal approach for the regioselective production of Z-retinoids. The most effective catalytic system was comprised of a palladium complex with labile ligands. Several mechanistic studies, including isotopic H/D exchange and state-of-the-art quantum chemical calculations using coupled cluster methods indicate that the isomerization is initiated by catalyst dimerization followed by the formation of a cyclic, six-membered chloropalladate catalyst-substrate adduct, which eventually opens to produce the desired Z-isomer. The synthetic development described here, combined with thorough mechanistic analysis of the underlying chemistry, highlights the use of readily available transition metal-based catalysts in straightforward formats for gram-scale drug synthesis.
Process for preparation of allyl sulfone derivatives and intermediates for the preparation
-
Page 8, (2010/02/06)
The present invention relates to a process for producing an allyl sulfone derivative represented by the formula (3): wherein Ar is an optionally substituted aryl group, and the corrugated line means either one of E/Z geometrical isomers, or a mixture thereof, which is an intermediate for producing vitamin A, which process is characterized by reacting an aryl sulfinic acid or a salt thereof represented by the formula (2): ArSO2M (2) wherein Ar is as defined above, and M is hydrogen atom, sodium atom or potassium atom, with an allyl halide derivative represented by the formula (1): wherein X is a halogen atom, and Ar and the corrugated line are as defined above.
Preparation of (7Z) - and (7Z,11Z) - Vitamin A
Soukup,Widmer
, p. 4117 - 4118 (2007/10/02)
An efficient access to (7Z)- and (7Z,11Z)-vitamin A is described. Following the addition of a C6-acetylenic building block to 2,6,6-trimethylcyclohexanone (2), dehydration of the tert. alcohol 3 and formation of the C15-Wittig salt, the (7Z)-geometry was introduced by partial hydrogenation of the triple bond over Raney-nickel. Following Wittig reaction with (E)-2-methyl-4-acetoxy-2-butenal gave a mixture of the title compounds 8 and 9 which could easily be separated.
