With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.131833-89-1,(S,S)-4,4′-Diisopropyl-4,5,4′,5′-tetrahydro[2.2]bioxazolyl,as a common compound, the synthetic route is as follows.
To a suspension of silver(I) triflate (415 mg, 1.62 mmol) in CH2Cl2 (5 mL) was added chloromethyl pivalate (243 mg, 1.62 mmol) and the resulting suspension stirred for 45 min. The supernatant was transferred to the bisoxazoline (250 mg, 1.12 mmol) and the mixture stirred at 40 C in the dark in a sealed Schlenk tube for 24 h. After cooling to ambient temperature, the reaction was quenched with MeOH (5 mL) and the mixture was concentrated in vacuo to afford a brown oil. Chromatographic purification (5% MeOH/CH2Cl2) and subsequent recrystallisation from CH2Cl2/Et2O gave the title compound 43 as a colourless solid (264 mg, 61%). inlMMLBox (c 0.5, CH2Cl2), lit.33 +55.0 (c 1.0, CH2Cl2); mp¡ì 155-157 C; deltaH (400 MHz, CDCl3) 8.73 (1H, s, NCHN), 5.07 (2H, dd, J 9.0, 7.9, CH2O), 4.98-4.93 (2H, m, CHCH2O), 4.83 (2H, dd, J 9.0 and 4.1, CH2O), 2.35-2.31 (2H, m, CHCH3), 1.03 (6H, d, J 6.9, CH3), 0.99 (6H, d, J 6.9, CH3); deltaC (100 MHz, CDCl3) 125.6 (NCO), 120.6 (q, J 321, CF3), 116.3 (NCHN), 79.1 (CH2), 63.9 (CHCH2), 31.1 (CHCH3), 17.6 (CH3) and 16.7 (CH3); 19F NMR (273 MHz, CDCl3) -78.6 (CF3). Data are in accordance with the literature.33, 131833-89-1
131833-89-1 (S,S)-4,4′-Diisopropyl-4,5,4′,5′-tetrahydro[2.2]bioxazolyl 11147594, acatalyst-ligand compound, is more and more widely used in various.
Reference£º
Article; Campbell, Craig D.; Concellon, Carmen; Smith, Andrew D.; Tetrahedron Asymmetry; vol. 22; 7; (2011); p. 797 – 811;,
Metal catalyst and ligand design
Ligand Template Strategies for Catalyst Encapsulation – NCBI