ChemInform Abstract: RK. SEK. AMINE MIT N‐ACYL‐(2,2‐DICHLOR‐VINYL)‐AMINEN UND N‐ACYL‐1‐CYAN‐(2,2‐DICHLOR‐VINYL)‐AMINEN

Abstract

Die Dichlorvinylamide (I) reagieren mit den Aminen (II) in Diäthyläther bei 25°C zu den Aminodichloräthylamiden (III).

A challenging synthesis of new 1,3,4‐thiadiazole derivatives starting from 2‐acylamino‐3,3‐dichloroacrylonitriles

“…The approach developed is of undeniable preparative significance, since the starting reagents are easy to obtain from the available adducts formed by carboxamides with chloral [2,18]. Moreover, the conversions 2→→5 and 2→→6 are quite straightforward and furnish the 1,3,4-thiadiazole derivatives unobtainable by the previously described methods [19].…”

“…It represents a particular case of a quite general synthetic route to 5-hydrazino-1,3-oxazole derivatives containing various electron acceptor groups, such as CN, C(O)OAlk, P(O)(OAlk) 2 , PPh + 3 , etc., at the position 4 [4,9,12].…”

“…To a solution of 1a-e (10 mmol) obtained by the known procedure [2,3] in EtOH (30 mL) was added hydrazine hydrate (35 mmol). The mixture was allowed to stand at r.t. for 24 h. After filtering off hydrazine hydrochloride, the solvent was evaporated in vacuo, and the residue was treated with H 2 O, filtered off, dried, and purified by recrystallization from EtOH or hexane to give 2a-e (Table 1).…”

“…Starting from these reagents, the preparative syntheses were elaborated for a number of functional derivatives c 2004 Wiley Periodicals, Inc. of 1,3-oxazole [1][2][3][4][5][6][7]10,11], 4H-imidazole [8], and 1,3,4-oxadiazole [9]. The present work addresses a new line in harnessing of 2-acylamino-3,3-dichloroacrylonitriles for the preparation of interesting 1,3,4-thiadiazole derivatives.…”

“…It is more than 30 years since two research teams, in Japan and Ukraine, started systematic studies on the conversions of 2-acylamino-3,3-dichloroacrylonitriles demonstrating unique properties as reagents for heterocyclizations [1][2][3][4][5][6][7][8][9][10][11]. Starting from these reagents, the preparative syntheses were elaborated for a number of functional derivatives c 2004 Wiley Periodicals, Inc. of 1,3-oxazole [1][2][3][4][5][6][7]10,11], 4H-imidazole [8], and 1,3,4-oxadiazole [9].…”