152120-59-7Relevant academic research and scientific papers
Catalytic Synthesis of Cyclic Guanidines via Hydrogen Atom Transfer and Radical-Polar Crossover
Ohuchi, Shunya,Koyama, Hiroki,Shigehisa, Hiroki
, p. 900 - 906 (2021)
Cyclic guanidines are found in many biologically active compounds and natural products. Further, the formation of the atypical seven-membered ring of cyclic guanidine remains challenging because of a lack of efficient preparation strategies and low yield. Herein, a catalytic synthetic method for cyclic guanidines was developed via transition-metal hydrogen atom transfer and radical-polar crossover. This mild and functional-group-tolerant process enabled the cyclization of alkenyl guanidines bearing common protective groups, such as Cbz and Boc groups. This powerful method provided not only typical five- and six-membered rings but also the atypical seven-membered ring. The derivatization of the products afforded various heterocycles. We also investigated the selective cyclization of monoprotected or heteroprotected (TFA and Boc) alkenyl guanidines and their further derivatizations.
Urethane protected derivatives of 1-guanylpyrazole for the mild and efficient preparation of guanidines
Bernatowicz, Michael S.,Wu, Youling,Matsueda, Gary R.
, p. 3389 - 3392 (2007/10/02)
Bis-urethane protected derivatives of 1-guanylpyrazole were prepared and found to readily react with relatively amines at room temperature to produce bis-protected guanidines in good yields. Simultaneous removal of both protecting groups from these products efficiently produced monosubstituted guanadines.
