1613027-35-2Relevant academic research and scientific papers
Sequential meta-C-H olefination of synthetically versatile benzyl silanes: Effective synthesis of meta-olefinated toluene, benzaldehyde and benzyl alcohols
Patra, Tuhin,Watile, Rahul,Agasti, Soumitra,Naveen, Togati,Maiti, Debabrata
, p. 2027 - 2030 (2016)
Tremendous progress has been made towards ortho-selective C-H functionalization in the last three decades. However, the activation of distal C-H bonds and their functionalization has remained fairly underdeveloped. Herein, we report sequential meta-C-H functionalization by performing selective mono-olefination and bis-olefination with late stage modification of the C-Si as well as Si-O bonds. Temporary silyl connection was found to be advantageous due to its easy installation, easy removal and wide synthetic diversification.
Remote meta-C–H Cyanation of Arenes Enabled by a Pyrimidine-Based Auxiliary
Bag, Sukdev,Jayarajan, Ramasamy,Dutta, Uttam,Chowdhury, Rajdip,Mondal, Rahul,Maiti, Debabrata
supporting information, p. 12538 - 12542 (2017/09/12)
An easily removable pyrimidine-based auxiliary has been employed for the remote meta-C?H cyanation of arenes. The scope of this Pd-catalyzed cyanation reaction using copper(I) cyanide as the cyanating agent was demonstrated with benzylsilanes, benzylsulfonates, benzylphophonates, phenethylsulfonates, and phenethyl ether derivatives. The method was utilized for the synthesis of pharmaceutically valuable precursors.
Experimental and Computational Exploration of para-Selective Silylation with a Hydrogen-Bonded Template
Maji, Arun,Guin, Srimanta,Feng, Sheng,Dahiya, Amit,Singh, Vikas Kumar,Liu, Peng,Maiti, Debabrata
supporting information, p. 14903 - 14907 (2017/10/30)
The regioselective conversion of C?H bonds into C?Si bonds is extremely important owing to the natural abundance and non-toxicity of silicon. Classical silylation reactions often suffer from poor functional group compatibility, low atom economy, and insufficient regioselectivity. Herein, we disclose a template-assisted method for the regioselective para silylation of toluene derivatives. A new template was designed, and the origin of selectivity was analyzed experimentally and computationally. An interesting substrate–solvent hydrogen-bonding interaction was observed. Kinetic, spectroscopic, and computational studies shed light on the reaction mechanism. The synthetic significance of this strategy was highlighted by the generation of a precursor of a potential lipophilic bioisostere of γ-aminobutyric acid (GABA), various late-stage diversifications, and by mimicking enzymatic transformations.
Remote para-C-H Functionalization of Arenes by a D-Shaped Biphenyl Template-Based Assembly
Bag, Sukdev,Patra, Tuhin,Modak, Atanu,Deb, Arghya,Maity, Soham,Dutta, Uttam,Dey, Aniruddha,Kancherla, Rajesh,Maji, Arun,Hazra, Avijit,Bera, Milan,Maiti, Debabrata
supporting information, p. 11888 - 11891 (2015/10/05)
Site-selective C-H functionalization has emerged as an efficient tool in simplifying the synthesis of complex molecules. Most often, directing group (DG)-assisted metallacycle formation serves as an efficient strategy to ensure promising regioselectivity. A wide variety of ortho- and meta-C-H functionalizations stand as examples in this regard. Yet despite this significant progress, DG-assisted selective para-C-H functionalization in arenes has remained unexplored, mainly because it involves the formation of a geometrically constrained metallacyclic transition state. Here we report an easily recyclable, novel Si-containing biphenyl-based template that directs efficient functionalization of the distal p-C-H bond of toluene by forming a D-shaped assembly. This DG allows the required flexibility to support the formation of an oversized pre-transition state. By overcoming electronic and steric bias, para-olefination and acetoxylation were successfully performed while undermining o- and m-C-H activation. The applicability of this D-shaped biphenyl template-based strategy is demonstrated by synthesizing various complex molecules.
