α-Bromination of β-Enamino Compounds Using K-10

Abstract

A series of a-bromo 3-amino-5,5-dimethylcyclohex-2en-1-ones 2a-g and a-bromo b-enamino compounds 4a, b have been conveniently prepared using NBS supported on montmorillonite (K-10). Other reaction conditions such as di-tert-butyl peroxide/NBS/CCl 4 , and Br 2 /CH 2 Cl 2 were also studied for 3-amino-5,5dimethylcyclohex-2-en-1-ones 1b, e, g resulting in a mixture of mono and di-brominated compounds 5b, f, g and 6b, e, g.

Cu-Catalyzed Synthesis of Novel Benzo[e]pyrazolo[1,5-c][1,3]-thiazine Derivatives

“…值得注意的是, 在底物 2 与异硫氰酸酯(3)反 应中, 当 2 中吡唑环上亲核的 N 原子进攻异硫氰酸酯(3) 中 N＝C＝S 基团的 C 原子形成中间体 5 之后, 在合适 的铜催化剂和配体存在下可通过两种方式发生关环反 应 (Scheme 2). 在方式 A 中, 发生 C-S 偶合反应生成 产物 4; 在方式 B 中 [17] , 发生 C-N 偶合反应生成产物 4', 该产物在我们的实验中未被检测到, 只有目标物 4 被获得, 显示出很高的区域选择性. 图 2 化合物 4b 的 X 射线衍射单晶结构 Figure 2 The X-ray structure of compound 4b…”

A new synthesis of functionalized dialkyl maleate and fumarate derivatives by addition of amines to dialkyl acetylenedicarboxylates in the presence of NBS or NCS

“…Although reaction of amine derivatives with activated unsaturated bonds were studied for the preparation of E or Z isomers of enaminoesters [19], but there is no report on the halogenation of this compounds under multicomponent reaction. On the other hand, the N-halosuccinimides, such as NBS and NCS, as inexpensive and readily reagents, have been used for the halogenation of b-enamine compounds [20]. Thus, as part of our current studies on broadening the scope of known MCRs to facilitate the synthesis of new enamine structures, we now report the reaction primary amines and dialkyl acetylenedicarboxylates in the presence of N-halosuccinimide, such as NCS and NBS (Scheme 1).…”

Microwave Assisted Montmorillonite KSF Clay Catalytic Synthesis Of 3-Benzyl-2,4-Diaryl-2,3,4,5-Tetrahydro-1h-Benzo [F][1,3,5]Triazepines And Its Anticorrosive Properties

“…6 Clay, less expensive recyclable alumino silicates, is a versatile reagent for organic synthesis. Due to its relative stability, non-toxic nature, inexpensive and its special catalytic attributes under heterogeneous reaction conditions, this reagent has been used for several organic transformations such as friedel-Crafts reaction, 7 sigmatrophic rearrangements, 8 bromination, 9 and oxidation. 10 Clay is also a wellknown electron-acceptor species and its interaction with variety of electron donors initiates the reaction, being an amphoteric it contains both acid and basic sites.…”