205495-66-5Relevant articles and documents
Preparation method of chiral Trost ligand
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Paragraph 0040-0060, (2021/03/24)
The invention relates to a preparation method of a chiral Trost ligand. The preparation method of the chiral Trost ligand comprises the following steps: mixing a solvent and a racemic Trost ligand toprepare a pretreatment solution; allowing the pretreatment liquid to flow into an adsorbent for adsorption treatment and then flow out, heating obtained effluent to 40 DEG C to 120 DEG C for heat treatment, conducting cooling, then performing adsorption treatment, and repeating the above cycle; after circulation is finished, collecting the adsorbent, conducting eluting with an eluent, and collecting eluate, wherein the adsorbent is macroporous resin. According to the preparation method, the R,R-configuration Trost ligand with an ee value higher than 99% can be prepared. Meanwhile, the preparation method of the chiral Trost ligand is simple in step and high in production efficiency, and can effectively avoid the wasting of S,S-configuration Trost ligands.
Synthesis of 7-Epi (+)-FR900482: An epimer of comparable anti-cancer activity
Trost, Barry M.,O'Boyle, Brendan M.
supporting information; experimental part, p. 1369 - 1372 (2009/04/10)
(Chemical Equation Presented) FR900482 is a potent anti-tumor therapeutic that has been investigated as a replacement candidate for the clinically useful Mitomycin C. Herein, we report synthesis and biological testing of 7-Epi (+)-FR900482, which demonstrates equal potency relative to the natural product against several cancer cell lines. Highlights of this work include utilization of our palladium-catalyzed DYKAT methodology and development of a Polonovski oxidative ring expansion strategy to yield this equipotent epimer in 23 linear steps.
Dynamic kinetic asymmetric transformation of diene monoepoxides: A practical asymmetric synthesis of vinylglycinol, vigabatrin, and ethambutol
Trost, Barry M.,Bunt, Richard C.,Lemoine, Remy C.,Calkins, Trevor L.
, p. 5968 - 5976 (2007/10/03)
The ability to perform a dynamic kinetic asymmetric transformation (DYKAT) using the palladium-catalyzed asymmetric allylic alkylation (AAA) is explored in the context of butadiene monoepoxide. The versatility of this commercially available, but racemic, four-carbon building block becomes significantly enhanced via conversion of both enantiomers into a single enantiomeric product. The concept is explored in the context of a synthesis of vinylglycinol with phthalimide as the nitrogen source. The success of the project required a new design of the ligand for palladium wherein additional conformational restraints were introduced. Thus, the phthalimide derivative of vinylglycinol was obtained in nearly quantitative yield and had an ee of 98% which, upon crystallization, was enhanced to > 99%. This one-step synthesis of a protected form of vinylglycinol provided short practical syntheses of the title compounds. Vigabatrin requires only four steps, and ethambutol six. The intermediate to the existing synthesis of ethambutol is available in 87% yield in three steps. (R)-Serine derives from oxidative cleavage of the double bond. The reaction of phthalimide and isoprene monoepoxide demonstrates the remarkable ability of the chiral ligands to control both regioselectivity and enantioselectivity and demonstrates the effectiveness of this protocol in creating a quaternary center asymmetrically.
