Enantioselective Cu-Catalyzed 1,4-Addition of Grignard Reagents to Cyclohexenone Using Taddol-Derived Phosphine-Phosphite Ligands and 2-Methyl-THF as a Solvent
Development of a Kilogram-Scale Process for the Enantioselective Synthesis of 3-Isopropenyl-cyclohexan-1-one via Rh/DTBM-SEGPHOS-Catalyzed Asymmetric Hayashi Addition Enabled by 1,3-Diol Additives
作者:Eric M. Simmons、Boguslaw Mudryk、Andrew G. Lee、Yuping Qiu、Thomas M. Razler、Yi Hsiao
DOI:10.1021/acs.oprd.7b00253
日期:2017.10.20
The development of a scalable process for the Rh-catalyZed asymmetric 1,4-addition of (isopropenyl)-pinacolboronate to 2-cyclohexen-1-one is reported. High-throughput ligand screening and initial optimization studies identified DTBM-SEGPHOS as an effective ligand along with a heptane/MeOH mixed solvent system. An inhibitory effect of the pinacol byproduct was identified, which could be mitigated by the addition of a 1,3-diol such as neopentyl glycol (npg). This process was demonstrated on 1 kg scale with 0.6 mol % Rh, producing (S)-1 in 82% yield and 99.6% ee, and was successfully scaled up at a vendor on 100 kg scale.
PHOTOLABILE PRO-FRAGRANCES
申请人:Henkel AG & Co. KGaA
公开号:US20180170849A1
公开(公告)日:2018-06-21
A method for producing photo-cleavable fragrance pre-cursors is described, which includes potential stereoselective method steps, agents containing the fragrance pre-cursors and the use of the fragrance pre-cursors for prolonging the scent impression in the agent and on surfaces treated with said agent.