Organic superbase-catalyzed oxidation of alkanethiols to dialkyl disulfides by elemental sulfur
作者:Zihan Zhang、Zhaoyang Xu、Rui Wang、Fei Li、Heng Jiang
DOI:10.1007/s11164-023-05082-8
日期:2023.10
Under atmospheric pressure and solvent-free conditions, organic superbase (SB) catalyzed the oxidation of alkanethiols (RSH) to dialkyl disulfides (R2S2) by using sulfur as oxidant was investigated. The results showed that amidines (DBU, DBN) and guanidines (BTMG, MTBD, TMG) exhibited significantly higher catalytic activity than common organic bases. Under the condition of 3.0 molar ratio of RSH/S
研究了在常压、无溶剂条件下,以硫为氧化剂,有机超强碱(SB)催化烷硫醇(RSH)氧化为二烷基二硫醚(R 2 S 2 )。结果表明,脒(DBU、DBN)和胍(BTMG、MTBD、TMG)的催化活性明显高于普通有机碱。在RSH/S摩尔比为3.0(RSH过量50 mol%)的条件下,( n -C 8 H 17 ) 2 S 2的收率可达99%~100%,SB用量为0.1 mol%,收率大于95% ( n -C 8 H 17 ) 2 S 2的产率即使使用 0.001 mol% SB 也可以获得。当RSH/S的摩尔比为2.1(RSH过量5mol%)时,目标产物R 2 S 2 (R=烷基、苯基)的收率仍高于90%。R 2 S 3是唯一的副产物,并且没有生成R 2 S 4 。SB对RSH的去质子化能力明显高于普通有机碱,RS -是催化反应中的关键活性物种。该合成方法具有操作简单、成本低廉的优点,并且适用于20-30