δ-Keto Aminoacrylonitriles and δ-Keto Aminoenones from 1-Pyrrolines, Cyanoacetylenes, and Acetylenic Ketones
作者:Boris A. Trofimov、Ludmila A. Oparina、Anastasiya G. Mal’kina、Nikita A. Kolyvanov、Igor A. Ushakov、Ivan V. Saliy、Konstantin A. Apartsin
DOI:10.1055/a-1742-2736
日期:2022.6
The ring-opening/functionalization of 1-pyrrolines by cyanoacetylenes or acetylenicketones (20–80 °C, MeCN, H2O) affords δ-keto aminoacrylonitriles and δ-keto aminoenones, mostly as the Z-isomers, in up to 85% yields. The synthesis involves C(2)–N bond cleavage in the intermediate hemiaminal resulting from the intermediate 1,3(4)-dipolar 1-pyrroline/acetylene complexes and water.
Catalyst-Free Annulation of Acylethynylpyrroles with 1-Pyrrolines: A Straightforward Access to Tetrahydrodipyrrolo[1,2-<i>a</i>:1′,2′-<i>c</i>]imidazoles
作者:Ludmila A. Oparina、Kseniya V. Belyaeva、Nikita A. Kolyvanov、Igor A. Ushakov、Maxim D. Gotsko、Lyubov’ N. Sobenina、Alexander V. Vashchenko、Boris A. Trofimov
DOI:10.1021/acs.joc.2c00476
日期:2022.8.5
Acylethynylpyrroles undergo facile (rt, MeCN or MeOH, 24–72 h) catalyst-free annulation with 1-pyrrolines to afford acylmethylenetetrahydrodipyrrolo[1,2-a:1′,2′-c]imidazoles in up to 93% yield and 90% E-stereoselectivity of the olefin moiety.
酰基乙炔基吡咯与 1-吡咯啉进行无催化剂环化(室温、MeCN 或 MeOH,24-72 小时),得到酰基亚甲基四氢二吡咯并[1,2- a :1',2' - c ]咪唑,收率高达 93%,产率为 90 % E-烯烃部分的立体选择性。
BEER-LIKE ALCOHOLIC BEVERAGE
申请人:Asahi Group Holdings, Ltd.
公开号:EP3543327A1
公开(公告)日:2019-09-25
The problem of the invention is to provide a beer-like alcoholic beverage with a reduced amount of digestible-carbohydrates, a reduced sensation of alcohol stimulation, and an excellent balance of beer-like flavors. The means for solving the problem is a beer-like alcoholic beverage wherein the amount of 4-vinyl guaiacol (4VG) is 10-200 ppb (w/v) in concentration, the amount of 2-acetyl-1-pyrroline (2AP) is less than 1 ppb (w/v) in concentration, the amount of digestible-carbohydrates is 2.0 g/100 mL or less in concentration, and the amount of alcohol is 4-10% (v/v) in concentration.
A general method for the synthesis of the most powerful naturally occurring Maillard flavors
作者:Claudio Fuganti、Francesco G. Gatti、Stefano Serra
DOI:10.1016/j.tet.2007.03.089
日期:2007.5
The natural flavors 2-acetyl-1-pyrroline 1a, 2-propionyl-l-pyrroline 1b, 2-acetyl-3,4,5,6-tetrahydropyridine 1c, 2-acetyl-2-thiazoline 1d, 2-propionyl-2-thiazoline 1e, and the artificial flavor 2-acetyl-5,6-dihydro-4H-1,3-thiazine if have been prepared by catalytic SeO2 oxidation of the corresponding cyclic imines 6a-c and sulfur cyclic immes 7a-c using TBHP as co-oxidant. The oxidation of the pyrrolines 1a and b is completely regioselective. Professional olfactory evaluation together with the odor threshold of the new flavor 1f is reported. (C) 2007 Elsevier Ltd. All rights reserved.
Reaction of organolithium reagents with lactim ethers: preparation of cyclic 2-alkyl imines or 2,2-dialkyl amines
作者:Charles A. Zezza、Michael B. Smith、Betsy A. Ross、Akwasi Arhin、Patricia L. E. Cronin