Changing stereoselectivity and regioselectivity in copper(i)-catalyzed 5-exo cyclization by chelation and rigidity in aminoalkyl radicals: synthesis towards diverse bioactive N-heterocycles
这项工作描述了带有未保护的NH-基团的β-卤代乙基烯丙基胺在铜(I)催化下的自由基环化成功,同时保持了催化剂的氧化还原活性。环化在0°C时发生区域和非对映选择性,并直接以高分离产率提供不同取代的1,3-反式-(NH)-吡咯烷。提出了庞大的铜络合物参与环化步骤,这可能是非对映选择性的可能原因。还证明了该产品在一步制备有用的4-氯-NH-吡咯中的合成应用。一种快速,温和且通用的方法,包括将三氯乙酸/二甲亚砜(CCl 3 CO 2 H-DMSO)溶液简单地添加到易于获取的N中开发了可耐受酸敏感性和高度失活的取代基的烯丙醛和酮亚胺,以获取胺前体。
Lewis Acid Mediated Vinyl-Transfer Reaction of Alkynes to<i>N</i>-Alkylimines by Using the<i>N</i>-Alkyl Residue as a Sacrificial Hydrogen Donor
作者:Chandi C. Malakar、Sara Stas、Wouter Herrebout、Kourosch Abbaspour Tehrani
DOI:10.1002/chem.201300469
日期:2013.10.11
A variety of N‐alkyl‐α,α‐dichloroaldimines were vinylated by terminal acetylenes in the presence of Lewis acids such as In(OTf)3 or BF3⋅OEt2 and hexafluoroisopropanol (HFIP) as an additive. The reaction proceeds at ambient temperature and leads to geometrically pure allylic β,β‐dichloroamines. This approach is complementary to previously reported transition‐metal‐catalyzed vinyl‐transfer methods, which
Synthesis and reactivity of alkenyl- and alkynyl-substituted β,β-dihalo-and β,β,β-trichloroamines
作者:Kourosch Abbaspour Tehrani、Sara Stas、Bart Lucas、Norbert De Kimpe
DOI:10.1016/j.tet.2009.01.034
日期:2009.3
beta,beta-Dihalo and beta,beta,beta-trichloroamines, obtained by Lewis acid-promoted Petasis-type reaction of alpha,alpha-dichlorinated and alpha,alpha,alpha-trichlorinated imines or reduction of alpha,alpha-dihaloaldimines, were subjected to a reactivity study and turned out to be remarkably stable compounds. In general, only the bases KO'Bu and NaOMe cause a 1,2-dehydrochlorination with formation of unsaturated alpha-chloroimines Or Unsaturated alpha,alpha-dichloroimines. Hydrolysis of the alpha-chloroimines with aqueous oxalic acid resulted in the formation of the corresponding unsaturated alpha-chloroketones. The reaction of simple beta,beta-dihaloamines with NaOMe and KO'Bu generated 2-haloprop-2-enylmines and 2,2-dimethoxypropylamines. (C) 2009 Elsevier Ltd. All rights reserved.
Shchepin, V. V.; Russkikh, N. Yu.; Lapkin, A. I., Journal of Organic Chemistry USSR (English Translation), 1982, vol. 18, p. 470 - 472
作者:Shchepin, V. V.、Russkikh, N. Yu.、Lapkin, A. I.
DOI:——
日期:——
Changing stereoselectivity and regioselectivity in copper(<scp>i</scp>)-catalyzed 5-<i>exo</i> cyclization by chelation and rigidity in aminoalkyl radicals: synthesis towards diverse bioactive N-heterocycles
作者:Sandhya Sadanandan、Dharmendra Kumar Gupta
DOI:10.1039/c9nj05166j
日期:——
Chelation, rigidity and carbon-radical positions in aminoalkyl precursors disturb the usual 2,4-trans diastereoselectivity and 5-exo mode in Cu(i)-catalyzed ATRC.
Direct and Stereoselective Synthesis of Diversely Substituted 2,4-<i>trans</i>-(NH)-Pyrrolidines by Copper(I)-Catalyzed Radical Cyclization at Low Temperature
作者:Ram N. Ram、Dharmendra Kumar Gupta
DOI:10.1002/adsc.201600844
日期:2016.10.20
applications of the products in the preparation of useful 4‐chloro‐NH‐pyrrole in a single step, has also been demonstrated. A quick, mild and general method involving simple addition of trichloroacetic acid/dimethyl sulfoxide (CCl3CO2H‐DMSO) solution to readily accessible N‐allylaldimines and ketimines tolerating acid‐sensitive and highly deactivating substituents was developed to access the amine precursors.
这项工作描述了带有未保护的NH-基团的β-卤代乙基烯丙基胺在铜(I)催化下的自由基环化成功,同时保持了催化剂的氧化还原活性。环化在0°C时发生区域和非对映选择性,并直接以高分离产率提供不同取代的1,3-反式-(NH)-吡咯烷。提出了庞大的铜络合物参与环化步骤,这可能是非对映选择性的可能原因。还证明了该产品在一步制备有用的4-氯-NH-吡咯中的合成应用。一种快速,温和且通用的方法,包括将三氯乙酸/二甲亚砜(CCl 3 CO 2 H-DMSO)溶液简单地添加到易于获取的N中开发了可耐受酸敏感性和高度失活的取代基的烯丙醛和酮亚胺,以获取胺前体。