Urethane protected derivatives of 1-guanylpyrazole for the mild and efficient preparation of guanidines
摘要:
Bis-urethane protected derivatives of 1-guanylpyrazole were prepared and found to readily react with relatively unreactive amines at room temperature to produce bis-protected guanidines in good yields. Simultaneous removal of both protecting groups from these products efficiently produced monosubstituted guanidines.
Efficient synthetic protocol for substituted guanidines via copper(I)-mediated intermolecular amination of isothiourea derivatives
作者:Hitoshi Ube、Daisuke Uraguchi、Masahiro Terada
DOI:10.1016/j.jorganchem.2006.06.046
日期:2007.1
Amination of S-methyl-N,N′-bis-Boc-isothiourea with either primary or sterically hindered secondary amines promoted by copper(I) chloride and K2CO3 gave N,N′-bis-Boc protected guanidines in good to excellent yields under mild reaction conditions.
用氯化铜(I)和K 2 CO 3促进的伯或空间位阻仲胺对S-甲基-N,N'-双-Boc-异硫脲进行胺化,得到N,N'-双-Boc保护的胍在温和的反应条件下具有优异的收率。
Synthesis of guanidines via the I2 mediated desulfurization of N,N′-di-Boc-thiourea
作者:Hao-Jie Rong、Cui-Feng Yang、Tao Chen、Yong-Qiang Wang、Bin-Ke Ning
DOI:10.1016/j.tetlet.2019.150970
日期:2019.8
The I2 mediated desulfurization of N,N′-di-Boc-thiourea was developed. Various primary amines, including sterically and electronically deactivated primary amines, were transformed into the corresponding bis-Boc protected guanidines under mild conditions.
Iodine-catalyzed guanylation of amines with<i>N</i>,<i>N</i>′-di-Boc-thiourea
作者:Hao-Jie Rong、Cui-Feng Yang、Tao Chen、Ze-Gang Xu、Tian-Duo Su、Yong-Qiang Wang、Bin-Ke Ning
DOI:10.1039/c9ob02014d
日期:——
Herein, we report that iodine-catalyzed guanylation of primary amines can be accomplished with N,N'-di-Boc-thiourea and TBHP to afford the corresponding guanidines in 40-99% yields. Oxidation of the HI byproduct by TBHP eliminates the need for an extra base to prevent the protonation of substrates and makes the reaction especially useful for both electronically and sterically deactivated primary anilines
A Convenient Preparation of Monosubstituted<i>N</i>,<i>N</i>′-di(Boc)-Protected Guanidines
作者:Brian Drake、Marcel Patek、Michal Lebl
DOI:10.1055/s-1994-25527
日期:——
1-H-Pyrazole-1-[N,N′-bis(tert-butoxycarbonyl)] carboxamidine (1) reacts under mild conditions with a number of amines and amino acids to give the respective protected guanidines in moderate to high isolated yields.
A Mild and Inexpensive Procedure for the Synthesis of N,N′-Di-Boc-Protected Guanidines
作者:Andrea Porcheddu、Lidia De Luca、Giampaolo Giacomelli
DOI:10.1055/s-0029-1218365
日期:2009.12
A novel and efficient synthetic procedure for converting a diverse set of amines to N,N′ -di-Boc-protected guanidines is described. The methodology comprises the use of cyanuricchloride (TCT) as activating reagent for di-Boc-thiourea. The employ of inexpensive TCT instead of classical HgCl 2 eliminates the environmental hazard of heavy-metal waste without appreciable loss of yield or reactivity. This