Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States.
J Agric Food Chem. 2021 Nov 3;69(43):12900-12908. doi: 10.1021/acs.jafc.1c04655. Epub 2021 Oct 25.
The development of chemicals to slowly release hydrogen sulfide would aid the survival of plants under environmental stressors as well as increase harvest yields. We report a series of dialkyldithiophosphates and disulfidedithiophosphates that slowly degrade to release hydrogen sulfide in the presence of water. Kinetics of the degradation of these chemicals were obtained at 85 °C and room temperature, and it was shown that the identity of the alkyl or sulfide group had a large impact on the rate of hydrolysis, and the rate constant varied by more than 10×. For example, using -butanol as the nucleophile yielded a dithiophosphate () that hydrolyzed 13,750× faster than the dithiophosphate synthesized from -butanol (), indicating that the rate of hydrolysis is structure-dependent. The rates of hydrolysis at 85 °C varied from a low value of 6.9 × 10 h to a high value of 14.1 h. Hydrogen sulfide release in water was also quantified using a hydrogen sulfide-sensitive electrode. Corn was grown on an industrial scale and dosed with dibutyldithiophosphate to show that these dithiophosphates have potential applications in agriculture. At a loading of 2 kg per acre, a 6.4% increase in the harvest yield of corn was observed.
开发能够缓慢释放硫化氢的化学品将有助于植物在环境胁迫下存活，并提高收获产量。我们报告了一系列二烷基二硫代磷酸酯和二硫代磷酸酯，它们在存在水的情况下缓慢降解以释放硫化氢。在 85°C 和室温下获得了这些化学物质的降解动力学，结果表明烷基或硫代基团的性质对水解速率有很大影响，速率常数变化超过 10 倍。例如，使用 -丁醇作为亲核试剂得到的二硫代磷酸酯（）比由 -丁醇合成的二硫代磷酸酯（）水解快 13,750 倍，这表明水解速率是结构依赖性的。85°C 下水解的速率从低值 6.9×10^-4 h 到高值 14.1 h 不等。还使用硫化氢敏感电极定量了水中的硫化氢释放。在工业规模上种植玉米，并向其施用过丁基二硫代磷酸酯，表明这些二硫代磷酸酯在农业中有潜在的应用。在每亩 2 公斤的用量下，观察到玉米的收获产量增加了 6.4%。
