In the chemical reaction process,reaction time,type of solvent,can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product.An updated downstream synthesis route of 24621-61-2,(S)-Butane-1,3-diol, as follows.24621-61-2
Example 4 Synthesis of Maytansinoid 4k,l (d) S-1,3-Di-O-p-toluenesulfonyl-butane 22: A solution of S-(-)-1,3-butanediol (21, 2.00 g (22.22 mmol) in a mixture of dry pyridine (40 mL) and dry toluene (60 mL) was treated with p-toluenesulfonyl chloride (12.70 g, 66.84 mmol) under argon at 0 C. After stirring at 0 C. for 5 min. followed by stirring at room temperature for 2 h, the mixture was evaporated under vacuum. The residue was redissolved in ethyl acetate, washed with 0.1 M aqueous NaHCO3, and saturated NaCl. The organic layer was separated, dried over MgSO4, filtered and evaporated. The residue was purified by chromatography over silica gel, eluding with 1:2 ethyl acetate/hexane to give 6.25 g (71%) of the title product 22 Rf=0.40 (1:1 EtOAc/hexane); 1H NMR (CDCl3) 7.76 (dd, 4H, J=1.0, 8.0 Hz), 7.35 (dt, 4H, J=0.4, 8.0+8.0 Hz), 4.70 (m, 1H), 4.03 (m, 1H), 3.94 (m, 1H), 2.46 (s, 6H), 1.92 (m, 2H), 1.26 (d, 3H, J=6.3 Hz); 13C NMR 145.17, 133.00, 130.11, 128.12, 127.91, 76.28, 66.21, 36.08, 21.86, 21.06; MS: 420.99 (M+Na)+.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 24621-61-2, and friends who are interested can also refer to it.
Reference£º
Patent; IMMUNOGEN, INC.; US2004/235840; (2004); A1;,
Synthesis and Crystal Structure of a Chiral?C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis
Chiral lanthanide(III) complexes of sulphur¨Cnitrogen¨Coxygen ligand derived from aminothiourea and sodium?D-camphor-¦Â-sulfonate