#RobSelects paper of the week J_A_C_S: Discovering approximate non-iterative algorithms for matrix-based electronic structure calculations via symbolic regression.
#compchem https://doi.org/10.1021/jacs.5c22323 #RobSelects paper of the week J_A_C_S: Discovering approximate non-iterative algorithms for matrix-based electronic structure calculations via symbolic regression.
#compchem https://doi.org/10.1021/jacs.5c22323 #RobSelects paper of the week
#J_A_C_S: Asymmetric Sm-catalyzed carbon-carbon coupling between alkenes and ketones forming tertiary alcohols.
#catalysis https://doi.org/10.1021/jacs.5c20884 #RobSelects paper of the week
#ScienceMagazine: Intramolecular peptide-catalyst-controlled stereoselective Michael addition between the enamine of an aldehyde and a ketovinylester.
#catalysis https://doi.org/10.1126/science.aec8992 #RobSelects paper of the week
#ScienceMagazine: Single-molecule vibrational spectroscopy via tunable femtosecond infrared excitation and cryogenic ultra-high vacuum scanning tunneling microscopy.
#physchem https://doi.org/10.1126/science.adz6643 #RobSelects paper of the week
#ChemicalScience: Electrochemical one-pot method for rhodium(II)-catalyzed cyclopropanation via in situ oxidation of tert-butyl hydrazones to diazo compounds.
#catalysis https://doi.org/10.1039/D5SC08940A #RobSelects paper of the week
#ACSCentSci: Systematic statistical analysis of 66,000 organic reactions from high-throughput experiments representative of pharmaceutical drug discovery.
#orgchem https://doi.org/10.1021/acscentsci.5c02031 #RobSelects paper of the week
#J_A_C_S: Excited-state triplet thiazole-2-thione biradicals as radical covalent catalysts for skeletal reorganization of N-sulfonyl vinylaziridines.
#catalysis https://doi.org/10.1021/jacs.5c20284 #RobSelects paper of the week
#J_A_C_S: Iridium-catalyzed reduction of beta-boryl amides triggers stereospecific cyclization to form aminocyclopropanes.
#catalysis https://doi.org/10.1021/jacs.5c21144 Catalytic Stereospecific Construction of Aminocyclopropanes from β-Boryl Amides
Iridium-catalyzed reduction of β-boryl amides with tetramethyldisiloxane affords iminium ions in situ. These reactive iminium ions are directly trapped by stereospecific (invertive) reaction with the boronate, delivering aminocyclopropanes (ACPs) in excellent yield, diastereoselectivity, and enantiospecificity. The reaction applies to both secondary and tertiary benzylic boronates, allylic boronates, and α-substituted boronates, giving access to many multiply substituted ACPs.
#RobSelects paper of the week
#ACSCatalysis: Nickel-catalyzed dehydroxylative cross-coupling of 1-substituted cyclopropanols and boronic acids via gamma-carbon-carbon activation.
#catalysis https://doi.org/10.1021/acscatal.5c07422 Dehydroxylative Noncanonical C–C Bond Arylation of Cyclopropanols: The Origin of Distal Selectivity via Remote Steric Effects
Precise activation of otherwise inert σ-bonds such as C(sp3)–C(sp3) and C(sp3)–OH remains a formidable challenge in homogeneous catalysis. While recent advances have harnessed cyclopropyl alcohol as a masked homoenolate or employed directing-group-assisted C–C bond insertion, these strategies exclusively follow conventional β-scission pathways. Herein, we report a noncanonical deoxygenative γ-C–C bond activation of cyclopropyl alcohols, enabling cross-coupling without the formation of homoenolate. Key to the transformation is tris(3,5-di-tert-butylphenyl)phosphine that creates a tris-ligated, pentacoordinate nickel transition state. The large cone angle directs oxidative addition to the distal C–C bond, while a low buried volume (% Vbur) preserves coordination sites. Competing homoenolate chemistry through β-scission is effectively suppressed by boronate masking under biphasic conditions. A series of mechanistic studies support a rate-determining γ-oxidative addition via a pentacoordinate transition state. The resulting π-allyl nickel intermediate undergoes intramolecular transmetalation in a highly regioselective C–C bond-forming event, forging a wide array of 1,1-dialkylethenes. This work establishes a distinct mechanistic framework for C–C bond activation, expanding the synthetic utility of cyclopropanol-based cross-coupling.
