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91.
Abdel-Aziz S. El-Ahl Fatty A. Amer Akram H. Elbeheery 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2226-2235
Abstract Unprecedented high-yield simple and mild conversion of primary aliphatic and aromatic thioamides into 5-substituted tetrazoles on treatment with a combination of tetrachlorosilane and sodium azide in refluxing acetonitrile has been achieved. Secondary acyclic, cyclic, and heterocyclic thioamides could also be transformed in high yields into 1-substituted, 1,5-disubstituted, or annulated tetrazoles under the same reaction condition. GRAPHICAL ABSTRACT 相似文献
92.
Chao Huangfu Liang Fu Yuzhi Li Xueling Li Haijun Du Jianshan Ye 《Electroanalysis》2013,25(9):2238-2243
In the present work, a sensitive, facile and disposable sensing platform for trace analysis of heavy metal ions was developed at the Bi modified graphene‐poly(sodium 4‐styrenesulfonate) composite film screen printed electrode (GR/PSS/Bi/SPE). The GR/PSS/Bi/SPE improved sensitivity and linearity due to the functionalization of graphene with negatively charged PSS providing more absorbing sites. The detection limit of the GR/PSS/Bi/SPE is found to be 0.042 µg L?1 for Cd2+ and 0.089 µg L?1 for Pb2+ with linear responses of Cd2+ and Pb2+ in the range of 0.5–120 µg L?1. Finally, the practical application was confirmed in real water with satisfactory results. 相似文献
93.
One-pot etherification reaction of aromatic and some aliphatic carbonyl compounds with organic halides in the presence of sodium hydride as a reducing reagent proceeded smoothly in dioxane, a polar solvent with higher boiling point, to provide desired ethers in moderate to high yields. 相似文献
94.
Núbia Boechat Jorge Carlos Santos da Costa Jorge de Souza Mendonça Karla Ceodaro Paes Elisa Lopes Fernandes Pedro Santos Mello de Oliveira 《合成通讯》2013,43(24):3187-3190
Some heteroaromatic esters were reduced to the corresponding alcohols by using a sodium borohydride–methanol system. The reduction was completed within 0.15–2.0 h in refluxing THF. The alcohol products were isolated after aqueous workup in moderate to excellent yield (48–97%). 相似文献
95.
Azim Ziyaei Halimjani 《合成通讯》2013,43(17):2271-2276
An efficient and simple method for the reduction of aldehydes, ketones and acid chlorides has been accomplished by using NaBH4–solid LiClO4 in mild conditions at ambient temperature with complete chemoselectivity in reduction of α,β‐unsaturated aldehydes and ketones. The reaction is fast with high yield and simple workup. 相似文献
96.
A novel synthetic utility of NaICl2 for the preparation of bis(4-dimethaminophenyl)arylmethanes and bis(4-dimethaminophenyl)alkanes is described. In the presence of an aqueous solution of NaICl2, the reaction of arenes with aromatic aldehydes gives corresponding triarylmethane derivatives regioselectively in moderate to good yields. The method is also useful for the preparation of diarylalkane derivatives by using aliphatic aldehydes. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications ® to view the free supplemental file. 相似文献
97.
Ketones and aldehydes are conveniently and rapidly reduced to the corresponding alcohols in good yields using sodium borohydride under sealed-tube microwave conditions in either 95% ethanol or water. In purely aqueous systems, highly aliphatic substrates are sluggish, but this can be overcome by introducing sodium dodecyl sulfate (SDS) at the critical micelle concentration. With a 2:1 substrate/borohydride ratio and a reaction temperature of 100 °C, reduction is typically complete within 1 min in 95% ethanol and 5 min in water/SDS. The methodology is well suited for parallel and combinatorial synthetic approaches. 相似文献
98.
Mohammad Ali Zolfigol Peyman Salehi Arash Ghorbani-Choghamarani Maliheh Safaiee Mozhgan Shahamirian 《合成通讯》2013,43(11):1817-1823
Silica chromate easily converts 1,4‐dihydropyridines to their corresponding pyridines in the presence of NaHSO4 · H2O and wet SiO2 in dichloromethane at room temperature in good to excellent yields. 相似文献
99.
A highly selective and efficient deprotection of the N‐t‐butoxy carbonyl (N‐Boc) group on indoles, pyrroles, indazoles, and carbolines has been achieved in high yields using a catalytic amount of NaOMe as a base in dry MeOH, at ambient temperature. 相似文献
100.
Primary thioamides are prepared in moderate to excellent yields by treating nitriles with sodium hydrogen sulfide and diethylamine hydrochloride in an appropriate solvent with mild heating. 相似文献