Stable chiral tertiary amine N‐oxide was obtained from the oxidation of hexahydro‐5 H ‐furo[2,3‐ b ]pyrrolo[1,2‐ d ][1,4]oxazin‐2(1 H )‐one by mCPBA. A Polonovski‐type intramolecular acyl transfer of N‐oxides resulted in the unexpected formation of a novel hexahydrofuro[3,2‐ d ]pyrrolo[2,1‐ b ]oxazol‐2(3 H )‐one motif, treatment of these carbinolamines with Lewis acid resulted in the generation of congested 3,9a‐methanopyrrolo[2,1‐ c ][1,4] oxazepine.
{"title":"Rigid Chiral Tertiary Amine N‐Oxides in the Synthesis of Linear Heterotriquinane and 3,9a‐Methanopyrrolo[2,1‐ c ][1,4]oxazepine Frameworks","authors":"Pei‐Jhen Lin, Ching‐Zong Luo, Hsiang‐Yu Chuang, Zi‐En Huang, Shih‐Chen Chen, Yu‐Jang Li","doi":"10.1002/ejoc.202500987","DOIUrl":"https://doi.org/10.1002/ejoc.202500987","url":null,"abstract":"Stable chiral tertiary amine N‐oxide was obtained from the oxidation of hexahydro‐5 <jats:italic>H</jats:italic> ‐furo[2,3‐ <jats:italic>b</jats:italic> ]pyrrolo[1,2‐ <jats:italic>d</jats:italic> ][1,4]oxazin‐2(1 <jats:italic>H</jats:italic> )‐one by mCPBA. A Polonovski‐type intramolecular acyl transfer of N‐oxides resulted in the unexpected formation of a novel hexahydrofuro[3,2‐ <jats:italic>d</jats:italic> ]pyrrolo[2,1‐ <jats:italic>b</jats:italic> ]oxazol‐2(3 <jats:italic>H</jats:italic> )‐one motif, treatment of these carbinolamines with Lewis acid resulted in the generation of congested 3,9a‐methanopyrrolo[2,1‐ <jats:italic>c</jats:italic> ][1,4] oxazepine.","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"135 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145554663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Herein, a transition‐metal‐free alkynylthiolation of tertiary α‐carbonyl bromides with 1,2,3‐thiadiazoles is reported. Those reactions involve the in situ generation of alkynylthiolate anions from 1,2,3‐thiadiazoles in the presence of a base and then their halogenophilic nucleophilic substitution (SN2X) reactions. The exceptionally mild reaction conditions, broad substrate scope, and excellent functional group tolerance highlight the utility of this method to prepare privileged motifs from readily available 1,2,3‐thiadiazoles and tertiary α‐carbonyl bromides feedstocks. Gram‐scale reaction and diverse synthetic transformations convincingly demonstrate the synthetic potential of this method.
{"title":"Transition‐Metal‐Free Alkynylthiolation of Tertiary α‐Carbonyl Bromides","authors":"Donghui Xing , Jinxi Huang , Jiaxiang Chen , Liangbin Huang","doi":"10.1002/ejoc.202500618","DOIUrl":"10.1002/ejoc.202500618","url":null,"abstract":"<div><div>Herein, a transition‐metal‐free alkynylthiolation of tertiary <em>α</em>‐carbonyl bromides with 1,2,3‐thiadiazoles is reported. Those reactions involve the in situ generation of alkynylthiolate anions from 1,2,3‐thiadiazoles in the presence of a base and then their halogenophilic nucleophilic substitution (S<sub>N</sub>2X) reactions. The exceptionally mild reaction conditions, broad substrate scope, and excellent functional group tolerance highlight the utility of this method to prepare privileged motifs from readily available 1,2,3‐thiadiazoles and tertiary <em>α</em>‐carbonyl bromides feedstocks. Gram‐scale reaction and diverse synthetic transformations convincingly demonstrate the synthetic potential of this method.</div></div>","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"28 42","pages":"Article e202500618"},"PeriodicalIF":2.7,"publicationDate":"2025-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144586345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Papita Behera, Laxmidhar Rout, Debendra K. Mohapatra
Transition metal‐catalyzed C( sp2 )–N cross‐coupling is a vital strategy in organic synthesis, enabling the efficient formation of N‐ aryl amines as key intermediates in pharmaceuticals, agrochemicals, and biologically active molecules. Precise control of reaction temperature is critical, as it significantly influences both product yield and the formation of byproducts. Conducting C( sp2 )–N cross‐coupling at room temperature offers notable advantages, including cost‐effectiveness, enhanced safety, and reduced environmental impact. This review summarizes literature from 1983 to 2025, highlighting transition metal‐catalyzed C( sp2 )–N cross‐coupling reactions and primarily involving palladium, copper, and nickel catalysts performed under mild, room‐temperature conditions. The review underscores the broad utility of these reactions across medicinal, agricultural, and industrial domains.
{"title":"Room‐Temperature C( sp 2 )N Bond Formation Using Pd, Cu, and Ni Catalysts","authors":"Papita Behera, Laxmidhar Rout, Debendra K. Mohapatra","doi":"10.1002/ejoc.202500913","DOIUrl":"https://doi.org/10.1002/ejoc.202500913","url":null,"abstract":"Transition metal‐catalyzed C( <jats:italic>sp</jats:italic> <jats:sup>2</jats:sup> )–N cross‐coupling is a vital strategy in organic synthesis, enabling the efficient formation of <jats:italic>N‐</jats:italic> aryl amines as key intermediates in pharmaceuticals, agrochemicals, and biologically active molecules. Precise control of reaction temperature is critical, as it significantly influences both product yield and the formation of byproducts. Conducting C( <jats:italic>sp</jats:italic> <jats:sup>2</jats:sup> )–N cross‐coupling at room temperature offers notable advantages, including cost‐effectiveness, enhanced safety, and reduced environmental impact. This review summarizes literature from 1983 to 2025, highlighting transition metal‐catalyzed C( <jats:italic>sp</jats:italic> <jats:sup>2</jats:sup> )–N cross‐coupling reactions and primarily involving palladium, copper, and nickel catalysts performed under mild, room‐temperature conditions. The review underscores the broad utility of these reactions across medicinal, agricultural, and industrial domains.","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"1 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145545860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A convenient new synthetic strategy was discovered for the synthesis of C3‐arylated imidazopyridines through alkylation of benzyl bromides with 2‐aminopyridines and base‐mediated condensation with diethyl oxalate. A series of C3‐arylated imidazopyridines was obtained in moderate to good yield. This protocol has the advantages of a mild reaction condition, broad substrate scope, and the absence of catalyst or additives.
{"title":"Synthesis of Ethyl 3‐phenylimidazo[1,2‐ a ]pyridine‐2‐carboxylate by Using 2‐Aminopyridines, Diethyl Oxalate, and Benzyl Bromides","authors":"Kaustav Dhara, Subrata Barick, Sandeep Chandrashekharappa","doi":"10.1002/ejoc.202500958","DOIUrl":"https://doi.org/10.1002/ejoc.202500958","url":null,"abstract":"A convenient new synthetic strategy was discovered for the synthesis of C3‐arylated imidazopyridines through alkylation of benzyl bromides with 2‐aminopyridines and base‐mediated condensation with diethyl oxalate. A series of C3‐arylated imidazopyridines was obtained in moderate to good yield. This protocol has the advantages of a mild reaction condition, broad substrate scope, and the absence of catalyst or additives.","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"70 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145545836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In recent years, thiocarbonyl compounds containing carbon–sulfur double-bond organic compounds (CS) possess unique structural and electronic properties that differentiate them from the well-studied carbonyl compounds (CO). Their polarized CS bond enhances their reactivity toward electrophiles and nucleophiles, making them valuable synthetic intermediates in organic transformations. These thiocarbonyl compounds readily participate in cycloaddition chemistry, radical, substitution, elimination, and addition reactions and serve as versatile building blocks in preparing various sulfur-containing heterocyclic compounds. The thiocarbonyl functional group is formed from carbonyl compounds through the use of phosphorus pentasulfide (P2S5 and dimer P4S10), H2S, and the most common reagent, i.e, Lawesson's reagent. They find medicinal and pharmaceutical chemistry applications where thiocarbonyl compounds exhibit various biological activities. Over the years, they have been explored as antiviral, anticancer, antibacterial, and antituberculosis agents and as treatments for hyperthyroidism. This article discusses recent developments in modern synthesis (2019–2025), reactivity, stability, and bio and material science applications of thiocarbonyl compounds, highlighting their increasing significance in sustainable chemistry and the development of novel therapeutics and novel optical materials.
{"title":"Recent Advances in the Synthesis and Applications of Thiocarbonyl Compounds","authors":"Jayshree Nandkumar Solanke, Deepika Sharma, Nalinikant Patra, Rambabu Dandela, Vasudevan Dhayalan","doi":"10.1002/ejoc.202500460","DOIUrl":"https://doi.org/10.1002/ejoc.202500460","url":null,"abstract":"In recent years, thiocarbonyl compounds containing carbon–sulfur double-bond organic compounds (CS) possess unique structural and electronic properties that differentiate them from the well-studied carbonyl compounds (CO). Their polarized CS bond enhances their reactivity toward electrophiles and nucleophiles, making them valuable synthetic intermediates in organic transformations. These thiocarbonyl compounds readily participate in cycloaddition chemistry, radical, substitution, elimination, and addition reactions and serve as versatile building blocks in preparing various sulfur-containing heterocyclic compounds. The thiocarbonyl functional group is formed from carbonyl compounds through the use of phosphorus pentasulfide (P<sub>2</sub>S<sub>5</sub> and dimer P<sub>4</sub>S<sub>10</sub>), H<sub>2</sub>S, and the most common reagent, i.e, Lawesson's reagent. They find medicinal and pharmaceutical chemistry applications where thiocarbonyl compounds exhibit various biological activities. Over the years, they have been explored as antiviral, anticancer, antibacterial, and antituberculosis agents and as treatments for hyperthyroidism. This article discusses recent developments in modern synthesis (2019–2025), reactivity, stability, and bio and material science applications of thiocarbonyl compounds, highlighting their increasing significance in sustainable chemistry and the development of novel therapeutics and novel optical materials.","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"96 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145531974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An efficient base-promoted synthetic approach has been developed for the synthesis of benzo[b]naphthooxepinones from (3-(acetylphenoxy)prop-1-yn-1-yl)benzaldehydes. The transformation proceeds via a base-mediated 7-exo-dig cyclization, followed by intramolecular aldol condensation and subsequent dehydration, resulting in the formation of a fused tricyclic ring system. This one-pot protocol affords a series of benzo[b]naphthooxepinone derivatives in moderate to good yields, offering a concise and environmentally benign route to these polycyclic scaffolds.
{"title":"Cesium Carbonate-Mediated Cascade Cyclization for the Efficient Synthesis of Fused Benzo[b]naphthooxepinone Derivatives","authors":"Saravanan Vijay, Sampath Thavaselvan, Kanniyappan Parthasarathy","doi":"10.1002/ejoc.202500862","DOIUrl":"https://doi.org/10.1002/ejoc.202500862","url":null,"abstract":"An efficient base-promoted synthetic approach has been developed for the synthesis of benzo[<i>b</i>]naphthooxepinones from (3-(acetylphenoxy)prop-1-yn-1-yl)benzaldehydes. The transformation proceeds via a base-mediated 7-<i>exo-dig</i> cyclization, followed by intramolecular aldol condensation and subsequent dehydration, resulting in the formation of a fused tricyclic ring system. This one-pot protocol affords a series of benzo[<i>b</i>]naphthooxepinone derivatives in moderate to good yields, offering a concise and environmentally benign route to these polycyclic scaffolds.","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"40 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145531976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Klaudia Chuchracka , Agnieszka Czapik , Marcin Kwit , Paweł Skowronek
The readily available, modular, and electronic circular dichroism (ECD)‐silent derivatives of terephthalaldehyde (the probes) have exhibited an induced optical activity (OA) upon condensation with chiral primary amines. The central unit of the probe serves as an amine binder by forming imine bonds and is flanked by two extended chromophoric units (the wings). Modification of the wings by diphenylamine or carbazole units affects the sterical and spectroscopic properties of the probes. An increase in sterical congestion within the probe core results in a change in the mechanism of OA induction. In the more congested systems, the point‐to‐axial chirality transmission from the chiral amine (the inducer) to the chromophoric system leads to the adaptation of helical conformation by “the wings” and the appearance of nonzero Cotton effects in the low‐energy part of the ECD spectrum. However, the sterically congested probes are sensitive to the chirality of the inducers but relatively indifferent to the differences in their structure. Thus, the chirality of the inducers triggers conformational change toward the thermodynamically preferred conformational diastereoisomer due to the probe's −1 to +1 operation scheme.
{"title":"Point‐to‐Axis Optical Activity Induction in Extended, Sterically Congested Chromophoric Systems","authors":"Klaudia Chuchracka , Agnieszka Czapik , Marcin Kwit , Paweł Skowronek","doi":"10.1002/ejoc.202500461","DOIUrl":"10.1002/ejoc.202500461","url":null,"abstract":"<div><div>The readily available, modular, and electronic circular dichroism (ECD)‐silent derivatives of terephthalaldehyde (the probes) have exhibited an induced optical activity (OA) upon condensation with chiral primary amines. The central unit of the probe serves as an amine binder by forming imine bonds and is flanked by two extended chromophoric units (the wings). Modification of the wings by diphenylamine or carbazole units affects the sterical and spectroscopic properties of the probes. An increase in sterical congestion within the probe core results in a change in the mechanism of OA induction. In the more congested systems, the point‐to‐axial chirality transmission from the chiral amine (the inducer) to the chromophoric system leads to the adaptation of helical conformation by “the wings” and the appearance of nonzero Cotton effects in the low‐energy part of the ECD spectrum. However, the sterically congested probes are sensitive to the chirality of the inducers but relatively indifferent to the differences in their structure. Thus, the chirality of the inducers triggers conformational change toward the thermodynamically preferred conformational diastereoisomer due to the probe's −1 to +1 operation scheme.</div></div>","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"28 41","pages":"Article e202500461"},"PeriodicalIF":2.7,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144288282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oleksandr V. Vashchenko , Hanna V. Ivanova , Tetyana V. Bondarchuk , Roman O. Doroshchuk , Ilona V. Raspertova , Alexander B. Rozhenko , Dmytro M. Volochnyuk , Serhiy V. Ryabukhin , Rostyslav D. Lampeka , Dmytro M. Khomenko
A series of 3‐(aminomethyl)‐5R‐1,2,4‐triazoles is synthesized in gram‐scale quantities starting from N‐(cyanomethyl)phthalimide and carboxylic acid hydrazides. The intramolecular cyclization of amidrazones to give 1,2,4‐triazolines is the key step. The main side products are 1,3,4‐oxadiazoles formed by a concurrent intramolecular condensation. Their amount depends on the steric and electronic nature of the substituent in the initial carboxylic acid hydrazide. Additionally, aminomethyl‐1,2,4‐triazole is modified by the introduction of different substituents at positions 1, 2, and 4 of the heterocyclic scaffold. Quantum chemical calculations demonstrate a fine balance of activation energy values for the key stages in the formation of the two isomeric products. In contrast to the previously derived mechanism, the participation of water, not ammonia, is required as a factor reducing the activation barriers for both reaction pathways.
{"title":"Synthesis of 3‐Aminomethyl‐5R‐1,2,4‐Triazoles by Cyclization of Amidrazones: Multigram Approach and Revised Reaction Mechanism","authors":"Oleksandr V. Vashchenko , Hanna V. Ivanova , Tetyana V. Bondarchuk , Roman O. Doroshchuk , Ilona V. Raspertova , Alexander B. Rozhenko , Dmytro M. Volochnyuk , Serhiy V. Ryabukhin , Rostyslav D. Lampeka , Dmytro M. Khomenko","doi":"10.1002/ejoc.202500646","DOIUrl":"10.1002/ejoc.202500646","url":null,"abstract":"<div><div>A series of 3‐(aminomethyl)‐5<em>R</em>‐1,2,4‐triazoles is synthesized in gram‐scale quantities starting from N‐(cyanomethyl)phthalimide and carboxylic acid hydrazides. The intramolecular cyclization of amidrazones to give 1,2,4‐triazolines is the key step. The main side products are 1,3,4‐oxadiazoles formed by a concurrent intramolecular condensation. Their amount depends on the steric and electronic nature of the substituent in the initial carboxylic acid hydrazide. Additionally, aminomethyl‐1,2,4‐triazole is modified by the introduction of different substituents at positions 1, 2, and 4 of the heterocyclic scaffold. Quantum chemical calculations demonstrate a fine balance of activation energy values for the key stages in the formation of the two isomeric products. In contrast to the previously derived mechanism, the participation of water, not ammonia, is required as a factor reducing the activation barriers for both reaction pathways.</div></div>","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"28 41","pages":"Article e202500646"},"PeriodicalIF":2.7,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145533415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A nickel‐catalyzed carboalkoxylation of the biphenylene CC σ‐bond with arylboronates and peroxides has been developed to form the corresponding ring‐opening difunctionalization products. The key to success is the use of acetal‐based, electron‐deficient peroxides, which enable the otherwise challenging CO cross coupling with nickel catalysts even under thermal conditions. A similar nickel catalysis is applicable to a related borylalkoxylation by replacement of arylboronates with danB–Bpin.
{"title":"Oxygen Electrophile‐Enabled Nickel‐Catalyzed Carboalkoxylation of Biphenylene CC σ‐Bond","authors":"Takeru Inoue , Koji Hirano","doi":"10.1002/ejoc.202500555","DOIUrl":"10.1002/ejoc.202500555","url":null,"abstract":"<div><div>A nickel‐catalyzed carboalkoxylation of the biphenylene CC σ‐bond with arylboronates and peroxides has been developed to form the corresponding ring‐opening difunctionalization products. The key to success is the use of acetal‐based, electron‐deficient peroxides, which enable the otherwise challenging CO cross coupling with nickel catalysts even under thermal conditions. A similar nickel catalysis is applicable to a related borylalkoxylation by replacement of arylboronates with danB–Bpin.</div></div>","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"28 41","pages":"Article e202500555"},"PeriodicalIF":2.7,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145068502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A metal‐free, base‐catalyzed double Michael diastereoselective [4 + 2] annulation reaction of para‐quinone methides with alkylidene pyrazolones and isatin‐derived N‐Boc ketimines or isatylidine malonitriles has been developed, leading to biologically inspired spiro‐heterocyclic derivatives under mild reaction conditions in a short reaction time. This strategy involves an atom‐economic transformation that generates three contiguous stereocenters, including a quaternary spiro‐center, in good to excellent yield (up to 94%) with excellent diastereoselectivities (up to >20:1 dr).
{"title":"Base‐Mediated Diastereoselective Aza/Oxa‐Michael Approach to Spiro‐Pyrazolone and Spiro‐Oxindole Derivatives Through [4 + 2] Spiro‐Annulation","authors":"Amol Savekar , Vishal Karande , Vaibhav Gawade , Suresh Waghmode","doi":"10.1002/ejoc.202500881","DOIUrl":"10.1002/ejoc.202500881","url":null,"abstract":"<div><div>A metal‐free, base‐catalyzed double Michael diastereoselective [4 + 2] annulation reaction of <em>para</em>‐quinone methides with alkylidene pyrazolones and isatin‐derived <em>N</em>‐Boc ketimines or isatylidine malonitriles has been developed, leading to biologically inspired spiro‐heterocyclic derivatives under mild reaction conditions in a short reaction time. This strategy involves an atom‐economic transformation that generates three contiguous stereocenters, including a quaternary spiro‐center, in good to excellent yield (up to 94%) with excellent diastereoselectivities (up to >20:1 <em>dr</em>).</div></div>","PeriodicalId":167,"journal":{"name":"European Journal of Organic Chemistry","volume":"28 41","pages":"Article e202500881"},"PeriodicalIF":2.7,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145533414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：