Cover Picture: Measuring the Relative Reactivity of the Carbon–Hydrogen Bonds of Alkanes as Nucleophiles (Angew. Chem. Int. Ed. 42/2018)

2018

A Quantitative Model for Alkane Nucleophilicity Based on C−H Bond Structural/Topological Descriptors

2020

A first quantitative model for calculating the nucleophilicity of alkanes is described. A statistical treatment was applied to the analysis of the reactivity of 29 different alkane C−H bonds towards in situ generated metal carbene electrophiles. The correlation of the recently reported experimental reactivity with two different sets of descriptors comprising a total of 86 parameters was studied, resulting in the quantitative descriptor‐based alkane nucleophilicity (QDEAN) model. This model consists of an equation with only six structural/topological descriptors, and reproduces the relative reactivity of the alkane C−H bonds. This reactivity can be calculated from parameters emerging from th…

Titelbild: Measuring the Relative Reactivity of the Carbon–Hydrogen Bonds of Alkanes as Nucleophiles (Angew. Chem. 42/2018)

2018

Functionalization of CnH2n+2Alkanes: Supercritical Carbon Dioxide Enhances the Reactivity towards Primary Carbon-Hydrogen Bonds

2015

The functionalization of the primary sites of alkanes is one of the more challenging areas in catalysis. In this context, a novel effect has been discovered that is responsible for an enhancement in the reactivity of the primary C-H bonds of alkanes in a catalytic system. The copper complex Cu(NCMe) (=hydrotris{[3,5-bis(trifluoromethyl)-4-bromo]-pyrazol-1-yl}borate) catalyzes the functionalization of CnH2n+2 with ethyl diazoacetate upon inserting the CHCO2Et unit into C-H bonds. In addition, the selectivity of the reaction toward the primary sites significantly increased relative to that obtained in neat alkane upon using supercritical carbon dioxide as the reaction medium. This was attribu…

Discovering Copper for Methane C–H Bond Functionalization

2015

The copper complex Tp(CF3)2,BrCu(NCMe) (1, Tp(CF3)2,Br = hydrotris((3,5-bis(trifluoromethyl)-4-bromo)-pyrazol-1-yl)borate) catalyzes the insertion of the CHCO2Et group (from ethyl diazoacetate N2CHCO2Et, EDA) into the C–H bonds of methane, in a homogeneous process that uses supercritical carbon dioxide (scCO2) as the reaction medium. Other light alkanes such as ethane, propane, and butane have been also functionalized with this copper-based catalyst, in the first example of the derivatization of the series of C1–C4 alkanes with this metal and a soluble catalyst.

Measuring the Relative Reactivity of the Carbon-Hydrogen Bonds of Alkanes as Nucleophiles

2018

We report quantitative measurements of the relative reactivities of a series of C-H bonds of gaseous or liquid CnH2n+2 alkanes (n = 1-8, 29 different C-H bonds) towards insitu generated electrophiles (copper, silver, and rhodium carbenes), with methane as the reference. This strategy surpasses the drawback of previous model reactions of alkanes with strong electrophiles suffering from C-C cleavage processes, which precluded direct comparison of the relative reactivities of alkane C-H bonds.

CCDC 1037192: Experimental Crystal Structure Determination

2016

Related Article: Riccardo Gava, Andrea Olmos, Bárbara Noverges, Teresa Varea, Eleuterio Álvarez, Tomás R. Belderrain, Ana Caballero, Gregorio Asensio, and Pedro J. Pérez|2015|ACS Catalysis|5|3726|doi:10.1021/acscatal.5b00718

CCDC 1037194: Experimental Crystal Structure Determination

2016

Related Article: Riccardo Gava, Andrea Olmos, Bárbara Noverges, Teresa Varea, Eleuterio Álvarez, Tomás R. Belderrain, Ana Caballero, Gregorio Asensio, and Pedro J. Pérez|2015|ACS Catalysis|5|3726|doi:10.1021/acscatal.5b00718

CCDC 1037193: Experimental Crystal Structure Determination

2016

Related Article: Riccardo Gava, Andrea Olmos, Bárbara Noverges, Teresa Varea, Eleuterio Álvarez, Tomás R. Belderrain, Ana Caballero, Gregorio Asensio, and Pedro J. Pérez|2015|ACS Catalysis|5|3726|doi:10.1021/acscatal.5b00718