138722-46-0Relevant academic research and scientific papers
Borane-Catalyzed, Chemoselective Reduction and Hydrofunctionalization of Enones Enabled by B-O Transborylation
Nicholson, Kieran,Langer, Thomas,Thomas, Stephen P.
supporting information, p. 2498 - 2504 (2021/04/13)
The use of stoichiometric organoborane reductants in organic synthesis is well established. Here these reagents have been rendered catalytic through an isodesmic B-O/B-H transborylation applied in the borane-catalyzed, chemoselective alkene reduction and formal hydrofunctionalization of enones. The reaction was found to proceed by a 1,4-hydroboration of the enone and B-O/B-H transborylation with HBpin, enabling catalyst turnover. Single-turnover and isotopic labeling experiments supported the proposed mechanism of catalysis with 1,4-hydroboration and B-O/B-H transborylation as key steps.
Visible-Light-Promoted Photocatalyst-Free Hydroacylation and Diacylation of Alkenes Tuned by NiCl2·DME
Zhao, Xinxin,Li, Bing,Xia, Wujiong
, p. 1056 - 1061 (2020/02/15)
Herein, we describe a visible light-promoted hydroacylation strategy that facilitates the preparation of ketones from alkenes and 4-acyl-1,4-dihydropyridines via an acyl radical addition and hydrogen atom transfer pathway under photocatalyst-free conditions. The efficiency was highlighted by wide substrate scope, good to high yields, successful scale-up experiments, and expedient preparation of highly functionalized ketone derivatives. In addition, this protocol allows for the synthesis of 1,4-dicarbonyl compounds through alkene diacylation in the presence of NiCl2·DME.
Ligand-controlled phosphine-free Co(II)-catalysed cross-coupling of secondary and primary alcohols
Zhang, Shi-Qi,Guo, Bin,Xu, Ze,Li, Hong-Xi,Li, Hai-Yan,Lang, Jian-Ping
, (2019/10/28)
Cobalt(II) complexes (5 mol% Co) bearing phosphine-free N?N?N pincer ligands efficiently catalyze C–C coupling of secondary and primary alcohols to selectively form α-alkylated ketones with a good functional group compatibility using NaOH (20 mol%) as a base at 120 °C. The NH group on the N?N?N–Co(II) precatalyst controls the activity and selectivity. This simple catalytic system is involved in the synthesis of quinolones via the dehydrogenative annulation of 2-aminobenzyl alcohols with secondary alcohols.
Electrochemical 1,4-reduction of α,β-unsaturated ketones with methanol and ammonium chloride as hydrogen sources
Huang, Binbin,Li, Yanan,Yang, Chao,Xia, Wujiong
supporting information, p. 6731 - 6734 (2019/06/17)
A sustainable, chemoselective 1,4-reduction of α,β-unsaturated ketones by means of an electrochemical method is presented, wherein the extremely inexpensive ammonium chloride (NH4Cl) is applied as the only additive. The reaction proceeds smoothly in the air at ambient temperature. Mechanistic studies reveal that both NH4Cl and solvent methanol work as hydrogen donors.
C?C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KOtBu: Unusual Regioselectivity through a Radical Mechanism
Kumar, Amit,Janes, Trevor,Chakraborty, Subrata,Daw, Prosenjit,von Wolff, Niklas,Carmieli, Raanan,Diskin-Posner, Yael,Milstein, David
supporting information, p. 3373 - 3377 (2019/02/14)
We report a C?C bond-forming reaction between benzyl alcohols and alkynes in the presence of a catalytic amount of KOtBu to form α-alkylated ketones in which the C=O group is located on the side derived from the alcohol. The reaction proceeds under thermal conditions (125 °C) and produces no waste, making the reaction highly atom efficient, environmentally benign, and sustainable. Based on our mechanistic investigations, we propose that the reaction proceeds through radical pathways.
Transition-Metal-Free Synthesis of Homo- and Hetero-1,2,4-Triaryl Benzenes by an Unexpected Base-Promoted Dearylative Pathway
Rehan, Mohammad,Maity, Sanjay,Morya, Lalit Kumar,Pal, Kaushik,Ghorai, Prasanta
, p. 7728 - 7732 (2016/07/07)
An unprecedented approach for the synthesis of homo- and hetero-1,2,4-triaryl benzenes has been developed using a simple base-mediated reaction of either α-aryl cinnamyl alcohols or α,γ-di-aryl propanones. The salient feature of this strategy involves the sequential hydride transfer, regiospecific condensation, regiospecific dearylation, and aromatization under metal-free reaction conditions. The synthesis of unsymmetrically substituted triphenylenes by oxidative coupling of the synthesized 1,2,4-triaryl benzenes has also been demonstrated.
Cobalt-catalyzed intermolecular hydroacylation of olefins through chelation-assisted imidoyl C-H activation
Yang, Junfeng,Seto, Yuan Wah,Yoshikai, Naohiko
, p. 3054 - 3057 (2015/05/20)
A low-valent cobalt catalyst generated from cobalt(II) bromide, a diphosphine ligand, and zinc powder promotes intermolecular hydroacylation of olefins using N-3-picolin-2-yl aldimines as aldehyde equivalents, which affords, upon acidic hydrolysis, ketone products in moderate to good yields with high linear selectivity. The reaction is applicable to styrenes, vinylsilanes, and aliphatic olefins as well as to various aryl and heteroaryl aldimines. The cobalt catalysis features a distinctively lower reaction temperature (60 °C) compared with those required for the same type of transformations catalyzed by rhodium complexes (typically 130-150°C).
Rhodium(I)-catalyzed arylation of β-chloro ketones and related derivatives through domino dehydrochlorination/conjugate addition
Jiang, Quanbin,Guo, Tenglong,Wang, Qingfu,Wu, Ping,Yu, Zhengkun
supporting information, p. 1874 - 1880 (2013/07/19)
Highly efficient arylations of β-chloro ketones and their ester and amide derivatives were achieved by means of domino dehydrochlorination/Rh(I)- catalyzed conjugate addition. In situ generated vinyl ketones and their analogues were identified as the reaction intermediates. The present synthetic protocol provides a concise route to (chiral) β-aryl ketones, esters, and amides. Copyright
Green alcohol couplings without transition metal catalysts: Base-mediated β-alkylation of alcohols in aerobic conditions
Allen, Laura J.,Crabtree, Robert H.
supporting information; experimental part, p. 1362 - 1364 (2010/09/16)
Benzylic secondary alcohols can be alkylated in good yields at the β-position with primary alcohols promoted by KOH and NaOH, eliminating the need for toxic and expensive transition metal catalysts.
