A one-pot preparation of cyanamide from dithiocarbamate using molecular iodine
作者:Jayashree Nath、Bhisma K. Patel、Latonglila Jamir、Upasana Bora Sinha、K. V. V. V. Satyanarayana
DOI:10.1039/b914283p
日期:——
method for the synthesis of cyanamides from dithiocarbamate salts via a double desulfurization strategy using molecular iodine is disclosed. Dithiocarbamates, by the action of iodine yield isothiocyanates in situ, which on treatment with aqueous NH3 give thioureas. The thioureas so generated undergo further oxidative desulfurization with I2 giving corresponding cyanamides in good yields. Environmental
A cascade process for directly converting nitriles (RCN) to cyanamides (RNHCN) <i>via</i> SO<sub>2</sub>F<sub>2</sub>-activated Tiemann rearrangement
作者:Guofu Zhang、Yiyong Zhao、Chengrong Ding
DOI:10.1039/c9ob01547g
日期:——
practical process for the direct conversion of nitriles to cyanamides was newly discovered and exhibited a wide substrate scope as well as great functional group-tolerability (36 examples). In this efficient strategy, the in situ generated amidoximes obtained from the reaction of nitriles with hydroxylamine subsequently underwent Tiemann rearrangement, producing the corresponding cyanamides with great
Copper(I)-Catalyzed Cascade Synthesis of 2-Arylsulfanyl- arylcyanamides
作者:Santosh K. Sahoo、Latonglila Jamir、Srimanta Guin、Bhisma K. Patel
DOI:10.1002/adsc.201000383
日期:2010.10.4
We have developed a ligand-assisted copper(I)-catalyzed two sequential heteroarylation sequence. An intramolecular S-arylation is followed by an intermolecular N-arylation leading to the direct synthesis of N-aryl-2-aminobenzothiazoles. In most cases however, the 2-arylsulfanyl-arylcyanamide was the major product obtained via an intramolecular CS bond formation, associated with CS bond breakage, followed
the Dimroth rearrangement in aqueous ethanolic sodium hydroxide gave exclusively the regioisomers, 2-(N-arylamino)quinazolin-4-ones. The regioselective synthesis of N-aryl-substituted 2-aminoquinazolin-4-ones can be further applied to the synthesis of benzimidazo[2,1-b]quinazolin-12-ones.
在对-TsOH存在下,在t- BuOH中,在回流下,邻氨基苯甲酸甲酯与N-芳基氰酰胺的反应主要得到3-芳基喹唑啉-4-酮。相比之下,相同的反应物与TMSCl在60°C的t- BuOH中反应,然后在乙醇氢氧化钠水溶液中进行Dimroth重排,仅得到区域异构体2-(N-芳基氨基)喹唑啉-4-酮。N-芳基取代的2-氨基喹唑啉-4-酮的区域选择性合成可以进一步应用于苯并咪唑并[2,1- b ]喹唑啉-12-酮的合成。