Catalyst-Free Synthesis of Chromane-Type N,O-Acetals via Intramolecular Addition of Phenols to Enamines
作者:Vitaly A. Osyanin、Dmitry V. Osipov、Irina V. Melnikova、Kirill S. Korzhenko、Irina A. Semenova、Yuri N. Klimochkin
DOI:10.1055/s-0040-1707209
日期:2020.12
Abstract A new strategy to 2-aminochromanes through catalyst-free cascade reaction of 3-trifluoroacetyl-4H-chromenes and 4H-chromene-3-carbaldehydes with cyclic secondary amines is presented. The reaction proceeds through subsequent 1,4- and 1,2-additions of amine, bimolecular elimination of trifluoroacetamide or formamide, and 6-exo-trig cyclization. The latter stage is a very rare example of addition
Recyclization of carbonyl-substituted 4H-chromenes and 1H-benzo[f]chromenes by the action of amidines and guanidine: a novel method for the synthesis of ortho-hydroxybenzylpyrimidines
作者:Yulia V. Popova、Darina V. Sakhnenko、Irina V. Arbuzova、Vitaly A. Osyanin、Dmitry V. Osipov、Yuri N. Klimochkin
DOI:10.1007/s10593-016-1969-5
日期:2016.10
A series of 2-[(pyrimidin-5-yl)methyl]phenols and 1-[(pyrimidin-5-yl)methyl]-2-naphthols have been accessed via the interaction of carbonyl-substituted 4H-chromenes and 1H-benzo[f]chromenes with amidines and guanidine in a reaction cascade initiated by the Michael reaction. It was established that in this transformation chromenes act as the synthetic equivalents of hydroxybenzylated α-formyl ketones
通过羰基取代的4 H-色烯与1 H的相互作用 已经获得了一系列的2-[(嘧啶-5-基)甲基]酚和1-[(嘧啶-5-基)甲基] -2-萘酚。由迈克尔反应引发的级联反应中,将am苯并[ f ]苯二甲基与am和胍联用。已经确定,在该转化中,色烯充当羟基苄基化的α-甲酰基酮或α-甲醛的合成等同物。
Synthesis of β-(о-hydroxybenzyl)pyridines by three-component condensation of ammonia, carbonyl-substituted 4Н-chromenes, and СН acids
作者:Dmitry V. Osipov、Vitaly A. Osyanin、Yuri N. Klimochkin
DOI:10.1007/s10593-019-02402-y
日期:2018.12
A series of pyridine derivatives containing a 2-hydroxybenzyl or (2-hydroxynaphthalen-1-yl)methyl substituent were obtained by treating carbonyl-substituted 4Н-chromenes and 1Н-benzo[f]chromenes with ammonia and 1,3-dicarbonyl compounds or aromatic ketones as a result of the carbo-Michael reaction, chromane ring opening, and cyclodehydration.
通过用氨和1,3-二羰基处理羰基取代的4Н苯甲基和1 benzo苯并[ f ]苯甲基,得到一系列含有2-羟基苄基或(2-羟基萘-1-基)甲基取代基的吡啶衍生物。碳-迈克尔反应,苯并二氢吡喃开环和环脱水的结果是化合物或芳族酮。
Oxa-[3+3] annulation of 1H-benzo[f]chromene-2-carbaldehydes and 2-naphthols: synthesis of 7aH,15H-benzo[f]benzo[5,6]chromeno[2,3-b]chromenes
作者:Irina А. Semenova、Vitaly А. Osyanin、Dmitry V. Osipov、Yuri N. Klimochkin
DOI:10.1007/s10593-021-02968-6
日期:2021.6
A method for the preparation of polycondensed chromeno[2,3-b]chromenes was developed based on the formal [3+3] cycloaddition reaction between 1H-benzo[f]chromene-2-carbaldehydes and 2-naphthols. In the case of resorcinol, the bisannulation product formed with the participation of both hydroxy groups was isolated.
基于1H-苯并[ f ]色烯-2-甲醛和2-萘酚之间的正式[3+3]环加成反应,开发了一种制备缩聚色烯[2,3- b ]色烯的方法。在间苯二酚的情况下,分离出两个羟基参与形成的双环化产物。
Studies in claisen rearrangements a novel oxidative rearrangement of 3-aryloxymethyl-(4H)-benzopyrans
3-Aryloxymethyl-(4H)-benzopyrans 2 have been found to undergo a novel Oxidative Claisenrearrangement. In contrast, the Claisenrearrangement of 3-aryloxymethyl-(2H)-benzopyrans afforded only the normal products 8.