Selectivity of nucleophilic addition to and substitution at isothiocyanatocarbonyl group. Reactions of 4-pentinoyl- and 2-(2-propinyl)-4-pentinoyl isothiocyanate with amines and methanol

1987 ◽  
Vol 52 (4) ◽  
pp. 995-1005 ◽  
Author(s):  
Peter Kutschy ◽  
Pavol Kristian ◽  
Milan Dzurilla ◽  
Dušan Koščík ◽  
Róbert Nádaskay

4-Pentinoyl isothiocyanate reacts with primary and secondary amines by either nucleophilic addition to N=C=S group to yield the corresponding thioureas, or a nucleophilic substitution at the carbonyl group to give 4-pentinoic acid amides. The less nucleophilic diphenylamine reacts selectively to afford the product of nucleophilic addition only. 2-(2-Propinyl)-4-pentinoyl isothiocyanate, having a sterically hindered carbonyl group, furnished with primary amines a mixture of amides and thioureas, whereas the bulkier secondary amines react selectively to form thioureas only. Both isothiocyanates afford with methanol as a nucleophile exclusively the corresponding O-methyl monothiocarbamates.

Author(s):  
Shuki Araki ◽  
Satoshi Hirose ◽  
Yoshikazu Konishi ◽  
Masatoshi Nogura ◽  
Tsunehisa Hirashita

The reactions of a 5-chloro-2,3-diphenyltetrazolium salt with amines have been examined. In the presence of an inorganic base such as NaHCO3, primary and secondary amines undergo a nucleophilic substitution to give the corresponding 5-aminotetrazolium salts. When triethylamine is used as a base, primary amines give 3-phenylazo-1,2,4-triazoles. A plausible dual-path mechanism is proposed for the formation of the triazoles via Type B mesoionic tetrazolium-5-aminides.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6544
Author(s):  
Ekaterina V. Bogdanova ◽  
Marina Yu. Stogniy ◽  
Kyrill Yu. Suponitsky ◽  
Igor B. Sivaev ◽  
Vladimir I. Bregadze

A series of novel cobalt bis(dicarbollide) based amidines were synthesized by the nucleophilic addition of primary and secondary amines to highly activated B-N+≡C–R triple bond of the propionitrilium derivative [8-EtC≡N-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)]. The reactions with primary amines result in the formation of mixtures of E and Z isomers of amidines, whereas the reactions with secondary amines lead selectively to the E-isomers. The crystal molecular structures of E-[8-EtC(NMe2)=HN-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)], E-[8-EtC(NEt2)=HN-3,3′-Co(1,2- C2B9H10)(1′,2′-C2B9H11)] and E-[8-EtC(NC5H10)=HN-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)] were determined by single crystal X-ray diffraction.


2008 ◽  
Vol 361 (11) ◽  
pp. 3109-3116 ◽  
Author(s):  
Silvia Mazzega Sbovata ◽  
Frazia Bettio ◽  
Christine Marzano ◽  
Mirto Mozzon ◽  
Roberta Bertani ◽  
...  

Synthesis ◽  
2019 ◽  
Vol 51 (12) ◽  
pp. 2579-2583 ◽  
Author(s):  
Andrii Gerasov ◽  
Alexander Shivanyuk ◽  
Volodymyr Fetyukhin ◽  
Oleg Lukin

The reactions of t-Boc-protected secondary and primary amines with difluorocarbene generated from trimethylsilyl (fluorosulfonyl)difluoroacetate [Me3SiOC(O)CF2SO2F] (TFDA) in toluene at 110 °C results in the replacement of t-Bu by difluoromethyl in the t-Boc group. This reaction can be carried out in the presence of CH2Br and COOMe moieties in the structure of the protected amine. In the example of a t-Boc-protected amine containing a C=C double bond, replacement of the t-Bu group and/or cyclodifluoropropanation takes place. Difluoromethyl esters are shown to react with primary and secondary amines yielding the corresponding ureas.


1990 ◽  
Vol 68 (9) ◽  
pp. 1544-1547 ◽  
Author(s):  
Ilan Pri-Bar ◽  
Howard Alper

Iodine is an effective promoter for the carbonylation of primary and secondary amines to ureas using palladium acetate as the catalyst and a base (e.g. K2CO3) in acetonitrile (3 h at 95 °C and 2.7 atm). Oxamides are formed in excellent yields when secondary amines are carbonylated in the presence of iodide ion and oxygen, while primary amines give ureas as the principal product at 95 °C, and oxamide at room temperature. Keywords: oxamides, ureas, double carbonylation, amines.


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