Secondary Benzylic Bromides Research Articles

Cobalt-Catalyzed Asymmetric Cross-Coupling Reaction of Fluorinated Secondary Benzyl Bromides with Lithium Aryl Boronates/ZnBr2.

A cobalt-catalyzed asymmetric cross-coupling of α-bromo-α-fluorotoluene derivatives with a variety of aryl zincates derived from lithium aryl n-butyl pinacol boronates and ZnBr2 under mild reaction conditions was described. In addition to mild reaction conditions, another advantage includes the compatibility of various common functional groups such as fluoride, chloride, bromide, cyano, or ester groups. Furthermore, this protocol was successfully applied to the enantioselective synthesis of three fluorinated derivatives of biologically active compounds or drug molecules.

Copper-catalyzed direct couplings of terminal alkynes with primary and secondary benzyl bromides

We have developed a facile Cu-catalyzed benzylation of terminal alkynes from easily available benzyl bromides.

Qilong Shen

Angewandte Chemie International EditionVolume 58, Issue 23 p. 7524-7524 Author ProfileFree Access Qilong Shen First published: 25 October 2018 https://doi.org/10.1002/anie.201811328AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract “My favorite food is steamed whole fish. If I were not a scientist, I would be a writer …” Find out more about Qilong Shen in his Author Profile. Qilong Shen The author presented on this page has published more than 10 articles in Angewandte Chemie in the last 10 years, most recently: “Enantioselective Construction of Trifluoromethoxylated Stereogenic Centers by a Nickel-Catalyzed Asymmetric Suzuki–Miyaura Coupling of Secondary Benzyl Bromides”: W. Huang, X. Wan, Q. Shen, Angew. Chem. Int. Ed. 2017, 56, 11986; Angew. Chem. 2017, 129, 12148. The work of Q. Shen has been featured on the back cover of Angewandte Chemie: “An Electrophilic Hypervalent Iodine Reagent for Trifluoromethylthiolation”: X. Shao, X. Wang, T. Yang, L. Lu, Q. Shen, Angew. Chem. Int. Ed. 2013, 52, 3457; Angew. Chem. 2013, 125, 3541. Date of birth: October 4, 1974 Position: Professor, Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry (SIOC), Chinese Academy of Sciences (CAS) E-mail: shenql@mail.sioc.ac.cn Homepage: http://shenqilong.sioc.ac.cn ORCID: 0000-0001-5622-153X Education: 1996 BS, Nanjing University 1999 MSc, SIOC, CAS 2002 MSc, University of Massachusetts, Dartmouth 2007 PhD with Prof. John F. Hartwig, Yale University 2007–2010 Postdoc with Prof. Jeffrey S. Moore, University of Illinois at Urbana-Champaign Awards: 2016 National Natural Science Fund for Distinguished Young Scholars, NSFC; 2018 Roche Chinese Young Investigator Award Current research interests: Organofluorine chemistry; electrophilic fluoroalkylating reagents; organometallic fluorine chemistry Hobbies: Hiking, reading My favorite food is steamed whole fish. If I were not a scientist, I would be a writer. If I won the lottery, I would set up my own research institute. The most important thing I learned from my parents is to stand up straight and do your best. I chose chemistry as a career because I was chosen as a member of my high-school chemistry olympiad team and I fell love with the subject. My greatest achievement has been the development of a family of electrophilic fluoroalkylating reagents. My favorite author (fiction) is Romain Rolland (who wrote the novel Jean Christophe). My favorite piece of music is Beethoven's “Moonlight” Sonata. My favorite quote is “If winter comes, can spring be far behind?” (Percy Bysshe Shelley). The most significant scientific advance of the last 100 years has been the discovery of the DNA structure. My 5 top papers: 1“Copper-Catalyzed Trifluoromethylation of Aryl and Vinyl Boronic Acids with An Electrophilic Trifluoromethylating Reagent”: T. Liu, Q. Shen, Org. Lett. 2011, 13, 2342. (Site-specific trifluoromethylation made easy.) 2“N-Trifluoromethylthiosaccharin: An Easily Accessible, Shelf-Stable, Broadly Applicable Trifluoromethylthiolating Reagent”: C.-F. Xu, B.-Q. Ma, Q. Shen, Angew. Chem. Int. Ed. 2014, 53, 9316; Angew. Chem. 2014, 126, 9470. (With a sweet component, this reagent makes trifluoromethylthiolated compounds readily accessible.) 3“Cooperative dual palladium/silver catalyst for direct difluoromethylation of aryl bromides and iodides”: Y. Gu, X. Leng, Q. Shen, Nat. Commun. 2014, 5, 5405. (A two-catalyst relay led to the first reported transition-metal-catalyzed difluoromethylation reaction.) 4“N-Difluoromethylthiophthalimide: A Shelf-Stable Electrophilic Regent for Difluoromethylthiolation”: D. Zhu, Y. Gu, L. Lu, Q. Shen, J. Am. Chem. Soc. 2015, 137, 10547. (A stable yet reactive “one-stop-shop” reagent for difluoromethylthiolation.) 5“Direct of Difluoromethylation of Alcohols with an Electrophilic Difluoromethylated Sulfonium Ylide”: J. Zhu, Y. Liu, Q. Shen, Angew. Chem. Int. Ed. 2016, 55, 9050; Angew. Chem. 2016, 128, 9196. (Umpolung reactivity in a sulfonium ylide—now it is electrophilic.) Volume58, Issue23June 3, 2019Pages 7524-7524 ReferencesRelatedInformation

Unsymmetrical CNN-palladacycles with geometry-constrained iminopyridyl ligands: an efficient precatalyst in Suzuki coupling for accessing 1,1-diarylalkanes from secondary benzylic bromides

We developed a series of unsymmetrical CNN palladacycles with geometry-constrained iminopyridyl ligands, which were used as efficient precatalysts for preparing diarylalkanes through Suzuki coupling.

Enantioselective Construction of Trifluoromethoxylated Stereogenic Centers by a Nickel‐Catalyzed Asymmetric Suzuki–Miyaura Coupling of Secondary Benzyl Bromides

Trifluoromethoxy-substituted stereogenic centers can be constructed with high enantioselectivity by a nickel-catalyzed Suzuki-Miyaura coupling of readily available α-bromobenzyl trifluoromethyl ethers with a variety of aryl pinacol boronates. The coupling proceeds under mild reaction conditions, and a variety of common functional groups, such as fluoride, chloride, bromide, ester, enolizable ketone, nitro, cyano, amino, and vinyl moieties, were well tolerated. Furthermore, the reaction can be easily scaled up to gram quantities without a decrease in enantioselectivity.

Enantioselective Construction of Trifluoromethoxylated Stereogenic Centers by a Nickel‐Catalyzed Asymmetric Suzuki–Miyaura Coupling of Secondary Benzyl Bromides

AbstractTrifluoromethoxy‐substituted stereogenic centers can be constructed with high enantioselectivity by a nickel‐catalyzed Suzuki–Miyaura coupling of readily available α‐bromobenzyl trifluoromethyl ethers with a variety of aryl pinacol boronates. The coupling proceeds under mild reaction conditions, and a variety of common functional groups, such as fluoride, chloride, bromide, ester, enolizable ketone, nitro, cyano, amino, and vinyl moieties, were well tolerated. Furthermore, the reaction can be easily scaled up to gram quantities without a decrease in enantioselectivity.

Cosolvent-Promoted O-Benzylation with Silver(I) Oxide: Synthesis of 1'-Benzylated Sucrose Derivatives, Mechanistic Studies, and Scope Investigation.

A cosolvent-promoted O-benzylation strategy with Ag2O was developed. The cosolvent consisting of CH2Cl2 and n-hexane can not only improve the reaction solubility for carbohydrates but also increase the benzylation efficiency. The formation of byproducts is greatly inhibited in the developed method. This method is simple, mild, and highly effective, and numerous 1'-benzylated sucrose derivatives were prepared including a photoreactive (trifluoromethyl)phenyldiazirine-based sucrose. The mechanisms of benzylation with primary and secondary benzyl bromides were also elaborated. Furthermore, the application scope with alcohols, glucose, and ribose derivatives was investigated.

ChemInform Abstract: Ligand‐Free Palladium‐Catalyzed Intramolecular Heck Reaction of Secondary Benzylic Bromides.

AbstractThe reaction works with beta‐hydrogen‐bearing secondary benzylic bromides.

Ligand-free palladium-catalyzed intramolecular Heck reaction of secondary benzylic bromides

A facile ligand-free palladium-catalyzed intramolecular Heck reaction of β-hydrogen-containing secondary benzylic bromides was developed, which affords pyrroline derivatives with good regioselectivities.

ChemInform Abstract: Palladium‐Catalyzed Cross‐Coupling Reaction of Secondary Benzylic Bromides with Grignard Reagents.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Palladium-Catalyzed Cross-Coupling Reaction of Secondary Benzylic Bromides with Grignard Reagents

A mild palladium-catalyzed Kumada-Corriu reaction of secondary benzylic bromides with aryl and alkenyl Grignard reagents has been developed. In the presence of the Xantphos ligand, the undesired beta-elimination pathway is minimized, affording the corresponding cross-coupling products in acceptable to good yields. The reaction proceeds with inversion of the configuration.

ChemInform Abstract: Enantioselective Nickel‐Catalyzed Cross‐Coupling Reactions of Trialkynylindium Reagents with Racemic Secondary Benzyl Bromides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Enantioselective Nickel‐Catalyzed Cross‐Coupling Reactions of Trialkynylindium Reagents with Racemic Secondary Benzyl Bromides

The first enantioselective sp-sp3 cross-coupling reaction between alkynyl organometals and racemic benzyl bromides is reported. The coupling is performed at room temperature by using NiBr2diglyme and (S)-(iPr)-Pybox as the catalytic system and trialkynylindium reagents as nucleophiles. The reaction is stereoconvergent, both enantiomers of the racemic benzyl bromide are converted into one enantiomer of the product, and stereospecific. The reaction takes place efficiently in good yields and with high atom economy, as the triorganoindium reagents transfer the three organic groups attached to indium (only 40 mol % of R3In is used).