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Pd0‐Catalyzed Intramolecular α‐Arylation of Sulfones: Domino Reactions in the Synthesis of Functionalized Tetrahydroisoquinolines 下载免费PDF全文
Prof.Dr. Daniel Solé Ferran Pérez‐Janer Dr. Raffaella Mancuso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4580-4584
A new strategy for the synthesis of tetrahydroisoquinolines based on the Pd0‐catalyzed intramolecular α‐arylation of sulfones is reported. The combination of this Pd‐catalyzed reaction with intermolecular Michael and aza‐Michael reactions allows the development of two‐ and three‐step domino processes to synthesize diversely functionalized scaffolds from readily available starting materials. 相似文献
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Palladium‐Catalyzed Oxidative Carbonylation of N‐Allylamines for the Synthesis of β‐Lactams 下载免费PDF全文
Wu Li Dr. Chao Liu Prof. Heng Zhang Keyin Ye Guanghui Zhang Wangzheng Zhang Zhengli Duan Prof. Shuli You Prof. Aiwen Lei 《Angewandte Chemie (International ed. in English)》2014,53(9):2443-2446
β‐Lactam scaffolds are considered to be ideal building blocks for the synthesis of nitrogen‐containing compounds. A new palladium‐catalyzed oxidative carbonylation of N‐allylamines for the synthesis of α‐methylene‐β‐lactams is reported. DFT calculations suggest that the formation of β‐lactams via a four‐membered‐ring transition state is favorable. 相似文献
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Erqing Li Prof. Dr. You Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(12):3520-3527
A novel strategy that involves phosphine‐catalyzed sequential [2+3] and [3+2] annulation reactions was developed. In this domino reaction, γ‐substituted allenoates were used as novel C4 synthons, and the bicyclic cyclopenta[b]dihydrofuran derivatives were produced in good to excellent diastereoselectivities and yields under mild conditions. Furthermore, preliminary studies on an asymmetric variant of this reaction proceeded with moderate enantioselectivity. 相似文献
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Benito Alcaide Prof. Dr. Pedro Almendros Dr. Teresa Martínez del Campo Dipl.‐Chem. M. Teresa Quirós Dipl.‐Chem. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3344-3346
First insights into the reaction between a Baylis–Hillman adduct and an allene moiety have been obtained from the novel domino heterocyclization/cross‐coupling reaction of α‐allenols and Baylis–Hillman acetates, which furnishes [(2,5‐dihydrofuran‐3‐yl)methyl]acrylate derivatives in moderate to good yields.
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Ming Chen Feipeng Liu Prof.Dr. Guangbin Dong 《Angewandte Chemie (International ed. in English)》2018,57(14):3815-3819
A direct and catalytic method is reported here for β‐arylation of N‐protected lactams with simple aryl iodides. The transformation is enabled by merging soft enolization of lactams, palladium‐catalyzed desaturation, Ar?X bond activation, and aryl conjugate addition. The reaction is operated under mild reaction conditions, is scalable, and is chemoselective. Application of this method to concise syntheses of pharmaceutically relevant compounds is demonstrated. 相似文献
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Facile Assembly of Benzo[b]naphtho[2,3‐d]azocin‐6(5 H)‐ones by a Palladium‐Catalyzed Double Carbometalation 下载免费PDF全文
The palladium‐catalyzed reaction of 2‐alkynylanilines with 2‐(2‐bromobenzylidene)cyclobutanone as an efficient route to 7,8‐dihydrobenzo[b]naphtho[2,3‐d]azocin‐6(5 H)‐ones was developed. The fused eight‐membered ring was constructed conveniently. During the reaction process, double carbometalation was involved, which resulted in excellent selectivity with the formation of three new bonds. This transformation is highly efficient and leads to fused polycycles in good to excellent yields with good functional group tolerance. 相似文献
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Benito Alcaide Prof. Dr. Pedro Almendros Dr. Teresa Martínez del Campo Rocío Carrascosa 《化学:亚洲杂志》2008,3(7):1140-1145
A mild, palladium(II)‐catalyzed reaction of α‐allenols with α‐allenic esters in a heterocyclization/cross‐coupling sequence, applicable to a wide range of substitution patterns, has been developed for the preparation of 2,3,4‐trifunctionalized 2,5‐dihydrofurans. Our studies indicate high levels of chemo‐ and regiocontrol. The possibility of using optically active substrates as well as substrates of increased steric demand, such as tertiary α‐allenols, makes this novel sequence of heterocyclization/cross‐coupling an attractive method in organic synthesis. The current mechanistic hypothesis invokes a regiocontrolled palladium(II)‐mediated intramolecular oxypalladation of the free allenol component, that then undergoes a cross‐coupling reaction with the allenic ester partner, followed by a trans‐β‐deacyloxypalladation with concomitant regeneration of the PdII species. 相似文献
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Lawrence L. W. Cheung Andrei K. Yudin Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):4100-4109
In this contribution, aminocyclobutanes, as well as eight‐membered enamide rings, have been made from N‐vinyl β‐lactams. The eight‐membered products have been formed by a [3,3]‐sigmatropic rearrangement, whereas the aminocyclobutanes have been derived from a domino [3,3]‐rearrangement/6π‐electrocyclisation process. The aminocyclobutanes have been obtained in a highly diastereoselective fashion. The cyclobutane ring system tolerates fusion even if adjacent quaternary centres are present. Systems containing up to four fused rings are readily accessible. The reaction profile has been investigated by using Gaussian 03. This study suggests that two reaction pathways for aminocyclobutane formation are possible. In one pathway the [3,3]‐sigmatropic rearrangement is the rate‐limiting step and in the second pathway the electrocyclisation is rate limiting. Taken together, these reactions should facilitate the construction of fused heterocycles. 相似文献
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Haoquan Li Dr. Wanfang Li Dr. Anke Spannenberg Dr. Wolfgang Baumann Dr. Helfried Neumann Prof. Dr. Matthias Beller Prof. Dr. Xiao‐Feng Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(28):8541-8544
Combining commercially available bromoanilines and bromobenzonitriles in a novel double carbonylation process allows for a straightforward synthesis of isoindolo[1,2‐b]quinazoline‐10,12‐diones. At least five different C?C and/or C?N bonds are selectively formed in this 3‐component reaction, which likely proceeds through sequential carbonylation–cyclization–isomerisation–carbonylation steps. Notably, two molecules of CO are inserted in this highly efficient palladium‐catalyzed process. 相似文献
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Domino Pd0‐Catalyzed C(sp3)–H Arylation/Electrocyclic Reactions via Benzazetidine Intermediates 下载免费PDF全文
Ronan Rocaboy Dr. David Dailler Florian Zellweger Dr. Markus Neuburger Dr. Christophe Salomé Dr. Eric Clot Prof. Dr. Olivier Baudoin 《Angewandte Chemie (International ed. in English)》2018,57(37):12131-12135
The Pd0‐catalyzed C(sp3)‐H arylation of 2‐bromo‐N‐methylanilides leads to unstable benzazetidine intermediates that rearrange to benzoxazines through 4π electrocyclic ring‐opening and 6π electrocyclization. The introduction of a bulky, non‐activatable amide group on the nitrogen atom was key to favor the challenging reductive elimination step and disfavor undesired reaction pathways. 相似文献
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Palladium‐Catalyzed Carbonylative Reactions of 1‐Bromo‐2‐fluorobenzenes with Various Nucleophiles: Effective Combination of Carbonylation and Nucleophilic Substitution 下载免费PDF全文
Jianbin Chen Dr. Kishore Natte Dr. Helfried Neumann Prof. Xiao‐Feng Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16107-16110
A systematic study on the carbonylative transformation of 1‐bromo‐2‐fluorobenzenes with various nucleophiles has been performed. Different types of double nucleophiles, such as N?N, N?C, O?C, and N?S, can be effectively applied as coupling partners. The corresponding six‐membered heterocycles were isolated in moderate to good yields. 相似文献
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Stereoselective Synthesis of Chiral Polycyclic Indolic Architectures through Pd0‐Catalyzed Tandem Deprotection/Cyclization of Tetrahydro‐β‐carbolines on Allenes 下载免费PDF全文
Valérian Gobé Dr. Xavier Guinchard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8511-8520
Enantioenriched N‐allyl tetrahydro‐β‐carbolines were prepared by chiral phosphoric acid‐catalyzed Pictet–Spengler reactions. The compounds undergo Pd0‐catalyzed cyclizations through a tandem deprotection/cyclization process. The regioselectivity of the attack is controlled by the chain length and by the substitution pattern of the allene function. Products resulting from 5‐exo‐ or 6‐exo‐attack were obtained with diastereoisomeric ratio up to 95:5. Azepinopyrrido[3,4‐b]indoles were obtained by 7‐endo‐cyclizations. 相似文献
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A novel palladium‐catalyzed domino reaction of 1‐bromo‐2‐(cyclopropylidenemethyl)benzene and 2‐alkynylbenzenamine is reported, which generates 2‐(naphthalen‐2‐yl)benzenamines and 5H‐indeno[1,2‐c]quinolines via 6‐endo and 5‐exo cyclization, respectively. The regioselectivity for the final outcome can be affected by phosphine and N‐heterocyclic carbene ligands. 相似文献