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1.
利用二氯代磷酰基异氰酸酯与4,6-二甲氧基-2-氨基嘧啶的加成反应合成了中间体N-(4,6-二甲氧基嘧啶-2-基)-N'-二氯代磷酰基脲(Ⅰ).Ⅰ与2倍的醇或胺反应得到对称双取代磷酰基脲类化合物Ⅱa_Ⅱi;Ⅰ与1倍的胺反应得到氯代磷酰基脲类化合物Ⅲa_Ⅲe,再与1倍的醇反应则得到不对称双取代磷酰基脲类化合物Ⅳa_Ⅳg.生物活性测定结果表明,化合物Ⅱ、Ⅲ和Ⅳ均显示一定除草活性. 相似文献
2.
Anna Matveeva Zoya Starikova Margarita Passechnik Irina Odinets Tatyana Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8-9)
The enols R 1 R 2 P(E)(CN)C = CR 3 OH (E = O or S) gave in solutions either neutral metal complexes ML x or M(OH) y L x . The anionic ambidentate ligands are coordinated through E and O atoms in solutions, and O, E, and N atoms in in crystals. 相似文献
3.
Jochen Münchenberg Jens R. Goerlich Axel K. Fischer Peter G. Jones Reinhard Schmutzler 《无机化学与普通化学杂志》1996,622(2):348-354
Synthesis, Structure, and some Reactions of N-(N′,N′,N″,N″-tetramethyl)guanidinyl-substituted Phosphoryl Compounds The tetramethylguanidinyl-substituted phosphoryl compounds 1 – 10 were prepared in the reaction of the appropriate chlorophosphoryl compounds with either N′,N′,N″,N″-tetramethylguanidine (HTMG) or N-trimethylsilyl-(N′,N′,N″,N″-tetramethyl)guanidine (TMSTMG). With methyl iodide 1 reacted with N-alkylation to give the ammonium salt 11. 1 reacted with BF3 · Et2O at both imino nitrogen atoms with formation of the bis-BF3-adduct 12 . The X-ray structure determination of phenylphosphonic acid-bis(N′,N′,N″,N″-tetramethylguanidinide) 3 shows shortened PN-bonds and widened PNC-angles, consistent with the partial double bond character of the PN-bond. 相似文献
4.
A series of novel phthalic diamide derivatives containing 1,2,3‐triazole moiety were synthesized using one‐pot click chemistry approach and characterized by 1H NMR and HRMS. The insecticidal activity against armyworm (Mythimna separata), Tetranychu scinnabarinus and cowpea aphid (Aphis craccivora) was evaluated. Compounds 4II‐a and 4II‐i showed 50% insecticidal activity against armyworm (Mythimna separata) at the concentration of 4 mg/L and one‐third of the compounds had moderate activity against Tetranychus cinnabarinus at 500 mg/L. 相似文献
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Three new A,C-diamide bridged p-tert-butylcalix[6]arenes were synthesized from p-tert-butylcalix[6]arenes by bridging ClCH2CONH(CH2)nNHCOCH2Cl(n=3,4,6) in acetonitrile using K2CO3 as a base in 17%-25% yields.It was found that the bridged calix[6]arenes with shorter bridges (n=2,3,4 in N′,N′-bischloroacetodiamines) adopt cone conformation, but the last one (n=6) adopts alternate conformation, i.e., accompanying the lengthening of bridge, the conformation of A,C-bridged calix[6]arenes changes from cone to alternate. 相似文献
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A simple procedure for the preparation of phosphoryl chlorofluorides, POFCl2 and POF2Cl, by chlorination of the appropriate potassium fluorophosphates, K2PO3F and KPO2F2, respectively, with PCl5 is described. The analogous bromination with PBr5 gives POFBr2 and POF2Br. However, due to low yields and high content of impurities, this method is not suitable for the synthesis of the former compound. Both chlorofluorides were crystallized from the melt at low temperatures and their crystal structures were determined by X‐ray diffraction at ?153 °C. Distorted tetrahedral molecules of POFCl2 are only weakly associated through intermolecular O···Cl contacts forming infinite chains similarly as in crystalline POCl3. In POF2Cl, however, the chains are formed by the O···P contacts, and an additional P–O···Cl bridging leads to their linkage into a double‐chain structure. 相似文献
9.
《Magnetic resonance in chemistry : MRC》2003,41(8):567-576
1H, 13C and 15N NMR and electrospray ionization time‐of‐flight mass spectrometric characterizations of five lithocholate esters of piperazine diamides are described. Two of them are cholaphane‐type cyclic structures esterified with 2,2′‐bipyridine‐4,4 ′ ‐ and pyridine‐2,6‐dicarboxylic acid and the other three esters are open structures comprising two or four lithocholyl residues. The conformational preferences of the dimeric congeners were examined by using molecular modelling and variable‐temperature 1H NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
10.