- Convenient synthesis of various substituted homotaurines from alk-2-enamides
-
Various substituted homotaurines (=3-aminopropane-1-sulfonic acids) 6 were readily synthesized in satisfactory to good yields via the Michael addition of thioacetic acid to alk-2-enamides 3 (→4), followed by LiAlH4 reduction (→5) and performic acid oxidation (Scheme 1). The configuration of 'anti'-disubstituted homotaurine 'anti'-6h was deduced from the 3-(acetylthio)alkanamide (=S-(3-amino-1,2-dimethyl-3-oxopropyl) ethanethioate)'anti'-4h formed in the Michael addition, which was identified via the Karplus equation analysis, and confirmed by X-ray diffraction analysis. The current route is an efficient method to synthesize diverse substituted homotaurines, including 1-, 2-, and N-monosubstituted, as well as 1,2-, 1,N-, 2,N-, and N,N-disubstituted homotaurines (Table). Copyright
- Nai, Youfeng,Xu, Jiaxi
-
p. 1355 - 1365
(2013/08/23)
-
- Scope and limitations of a modified hantzsch reaction for the synthesis of oxazole-dehydroamino acid derivatives from dehydroamino acid amides
-
A variety of oxazole derivatives that possess an α,β-unsaturated substituent at the 2-position were conveniently synthesized in good yields via a Hantzsch-type reaction between dehydroamino acid amides and β-bromopyruvate derivatives. Furthermore, oxazole
- Nagaya, Akihiro,Yamagishi, Yoji,Yonezawa, Yasuchika,Akai, Shoji,Shin, Chung-Gi,Sato, Ken-Ichi
-
experimental part
p. 313 - 331
(2012/03/26)
-
- Aromatic borylation/amidation/oxidation: A rapid route to 5-substituted 3-amidophenols
-
5-Substituted 3-amidophenols are prepared by subjecting 3-substituted halobenzenes to an Ir-catalyzed aromatic borylation, followed by a Pd-catalyzed amidation, and finally an oxidation of the boronic ester intermediate. The entire C-H activation borylation/amidation/oxidation sequence can be accomplished without isolation of any intermediate arenes. Usefully, amide partners can include lactams, carbamates, and ureas.
- Shi, Feng,Smith III, Milton R.,Maleczka Jr., Robert E.
-
p. 1411 - 1414
(2007/10/03)
-
- Stereospecific Nucleophilic Addition Reactions to Olefins. Addition of Thiols to α,β-Unsaturated Carboxylic Acid Derivatives
-
Stereospecific nucleophilic addition of thiols to derivatives of α,β-unsaturated carboxylic acids is described.The additions are carried out at room temperature in the presence of a catalytic amount of lithium thiolate and an excess of thiol as a proton source.Erythro and threo adducts are obtained with high diastereoselectivity from E and Z olefins, respectively.This anti addition suggests that the enolate generated by nucleophilic addition undergoes rapid protonation prior to conformational change in the intermediate.
- Miyata, Okiko,Shinada, Tetsuro,Ninomiya, Ichiya,Naito, Takeaki,Date, Tadamasa,et al.
-
p. 6556 - 6564
(2007/10/02)
-