^(31)PNMR谱表明,在4,5-二氧-2-硫-1,3,2,4-二氮二磷杂环戊烷类型化合物中,存在着顺式和反式两种异构体.顺式异构体化学位移出现在高场,~2J_(pp)偶全合常数较大;而反式异构体化学位移在低场,~2J_(pp)偶合常数较小.用Van der Waals排斥力...^(31)PNMR谱表明,在4,5-二氧-2-硫-1,3,2,4-二氮二磷杂环戊烷类型化合物中,存在着顺式和反式两种异构体.顺式异构体化学位移出现在高场,~2J_(pp)偶全合常数较大;而反式异构体化学位移在低场,~2J_(pp)偶合常数较小.用Van der Waals排斥力和Pπ-dπ反馈理论解释了以上现象,并讨论了其他取代基R、X对^(31)P—NMR化学位移的影响.展开更多
<正> A new type of diphosphorus heterocycles, 4,5- dioxo- 2- thio- 1,3, 2,4- diazadiphospholanes,has been synthesized by the condensation of carbamyl phosphoryl amidate and 4- substitutedphenyl phosphine dichlor...<正> A new type of diphosphorus heterocycles, 4,5- dioxo- 2- thio- 1,3, 2,4- diazadiphospholanes,has been synthesized by the condensation of carbamyl phosphoryl amidate and 4- substitutedphenyl phosphine dichloride, and then sulfurization. The cis- and trans-isomers of the com-pounds were separated by HPLC, and their structures were studied with1H NMR and31PNMR. It has been found that the cis- and trans-isomers have different chemical shifts (δ) anddifferent coupling constants. The preliminary bioassay shows that some of them possessstrong herbicidal activity.展开更多
文摘^(31)PNMR谱表明,在4,5-二氧-2-硫-1,3,2,4-二氮二磷杂环戊烷类型化合物中,存在着顺式和反式两种异构体.顺式异构体化学位移出现在高场,~2J_(pp)偶全合常数较大;而反式异构体化学位移在低场,~2J_(pp)偶合常数较小.用Van der Waals排斥力和Pπ-dπ反馈理论解释了以上现象,并讨论了其他取代基R、X对^(31)P—NMR化学位移的影响.
文摘<正> A new type of diphosphorus heterocycles, 4,5- dioxo- 2- thio- 1,3, 2,4- diazadiphospholanes,has been synthesized by the condensation of carbamyl phosphoryl amidate and 4- substitutedphenyl phosphine dichloride, and then sulfurization. The cis- and trans-isomers of the com-pounds were separated by HPLC, and their structures were studied with1H NMR and31PNMR. It has been found that the cis- and trans-isomers have different chemical shifts (δ) anddifferent coupling constants. The preliminary bioassay shows that some of them possessstrong herbicidal activity.