Cesium fluoride → 3-Amino-5-ethynyl N (2 (2 (2 methoxyethoxy)ethoxy)ethyl)benzamide

Participants

Reaction Steps

To the product from step (iii) above (1200 g, 2.59 mol) in MeCN (8.8 L) was added CsF (433.6 g, 2.85 mol). The reaction was stirred at RT overnight, after which HPLC analysis showed 1.7% product, 97.4% starting material. Additional CsF (420 g, 2.76 mol) was charged and the reaction stirred at RT overnight, whereupon HPLC analysis revealed 91.0% product, 4.4% starting material. The mixture was filtered and the filtrate concentrated in vacuo to give material which was 92.5% product, 0.7% starting material by HPLC. The residue was dissolved in DCM (3 L) and EtOAc (3 L), before being split into two equal portions. Each portion was passed through a silica pad (1.6 kg), eluting with EtOAc (50 L). The filtrates were combined and concentrated in vacuo. The crude material was washed with heptane (2×4 L) to remove silyl impurities. A total of 719 g of sub-title compound was isolated (83% assay by 1H NMR, 75% active yield, 597 g active).

Provenance & Evidence