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Abstract: Translating a homogenous catalyst into a heterogeneous catalyst requires a fundamental understanding of how the catalyst “fits” into the zeolite and how the reaction is influenced. Previous studies of bimetallic catalyst design identified a potent copper homobinuclear catalyst, [(L)Cu2(H)]+ for the selective decomposition of formic acid. Here, a close interplay between theory and experiment shows how to preserve this selective reactivity within zeolites. Gas‐phase experiments and DFT calculations showed that switching from 1,1‐bis(diphenylphosphino)‐methane ligand to the 1,8‐naphthyridine ligand produced an equally potent catalyst. DFT calculations show that this new catalyst neatly fits into a zeolite which does not perturb reactivity, thus providing a unique example on how “heterogenization” of a homogenous catalyst for the selective catalysed extrusion of carbon dioxide from formic acid can be achieved, with important application in hydrogen storage and in situ generation of H2. [ABSTRACT FROM AUTHOR]

Although the deleterious effects of ozone on the human respiratory system are well-known, many of the precise chemical mechanisms that both cause damage and afford protection in the pulmonary epithelial lining fluid are poorly understood. As a key first step to elucidating the intrinsic reactivity of ozone with proteins, its reactions with deprotonated cysteine [Cys−H]− are examined in the gas phase. Reaction proceeds at near the collision limit to give a rich set of products including 1) sequential oxygen atom abstraction reactions to yield cysteine sulfenate, sulfinate and sulfonate anions, and significantly 2) sulfenate radical anions formed by ejection of a hydroperoxy radical. The free-radical pathway occurs only when both thiol and carboxylate moieties are available, implicating electron-transfer as a key step in this reaction. This novel and facile reaction is also observed in small cys-containing peptides indicating a possible role for this chemistry in protein ozonolysis. [ABSTRACT FROM AUTHOR]

A combination of gas‐phase ion–molecule reaction experiments and theoretical kinetic modeling is used to examine how a salt can influence the kinetic basicity of organometallates reacting with water. [HC≡CLiCl]− reacts with water more rapidly than [HC≡CMgCl2]−, consistent with the higher reactivity of organolithium versus organomagnesium reagents. Addition of LiCl to [HC≡CLiCl]− or [HC≡CMgCl2]− enhances their reactivity towards water by a factor of about 2, while addition of MgCl2 to [HC≡CMgCl2]− enhances its reactivity by a factor of about 4. Ab initio calculations coupled with master equation/RRKM theory kinetic modeling show that these reactions proceed via a mechanism involving formation of a water adduct followed by rearrangement, proton transfer, and acetylene elimination as either discrete or concerted steps. Both the energy and entropy requirements for these elementary steps need to be considered in order to explain the observed kinetics. [ABSTRACT FROM AUTHOR]

A combination of gas‐phase ion–molecule reaction experiments and theoretical kinetic modeling is used to examine how a salt can influence the kinetic basicity of organometallates reacting with water. [HC≡CLiCl]− reacts with water more rapidly than [HC≡CMgCl2]−, consistent with the higher reactivity of organolithium versus organomagnesium reagents. Addition of LiCl to [HC≡CLiCl]− or [HC≡CMgCl2]− enhances their reactivity towards water by a factor of about 2, while addition of MgCl2 to [HC≡CMgCl2]− enhances its reactivity by a factor of about 4. Ab initio calculations coupled with master equation/RRKM theory kinetic modeling show that these reactions proceed via a mechanism involving formation of a water adduct followed by rearrangement, proton transfer, and acetylene elimination as either discrete or concerted steps. Both the energy and entropy requirements for these elementary steps need to be considered in order to explain the observed kinetics. [ABSTRACT FROM AUTHOR]

Mass spectrometry shows the way! MS analysis of silver salts treated with sodium borohydride in the presence of a bis(phosphino) ligand revealed the formation of novel silver hydride nanocluster cations instead of all silver nanocluster cations. This serendipitous discovery prompted the condensed‐phase synthesis, isolation, and characterization of [Ag3{(Ph2P)2CH2}3(μ3‐H)(μ3‐Cl)]BF4⋅0.5 CHCl3. [ABSTRACT FROM AUTHOR]

Mass spectrometry shows the way! MS analysis of silver salts treated with sodium borohydride in the presence of a bis(phosphino) ligand revealed the formation of novel silver hydride nanocluster cations instead of all silver nanocluster cations. This serendipitous discovery prompted the condensed‐phase synthesis, isolation, and characterization of [Ag3{(Ph2P)2CH2}3(μ3‐H)(μ3‐Cl)]BF4⋅0.5 CHCl3. [ABSTRACT FROM AUTHOR]

The mystery of why water and salt contaminants destroy organometallic reagents has been solved by G. N. Khairallah, G. da Silva, and R. A. J. O'Hair in their Communication on page 10979 ff. The addition of an individual salt molecule to an organometallic reagent dramatically enhances its reactivity towards water. This second metal center plays an active role in altering the fundamental chemical transformations that take place when water attacks the organometallic compound. [ABSTRACT FROM AUTHOR]

Mass Spectrometry Man saves the day! Traveling from his home on planet Gas Phase, he used his ESI‐MS powers to provide G. N. Khairallah, P. S. Donnelly, R. A. J. O'Hair, and co‐workers with vital information for their Communication on page 8391 ff. MS Man's powers revealed the formation of novel silver hydride nanocluster cations in silver salts reduced by sodium borohydride in the presence of a bis(phosphino) ligand, and led the way to the condensed‐phase synthesis, isolation, and characterization of [Ag3{(Ph2P)2CH2}3(μ3‐H)(μ3‐Cl)]BF4⋅0.5 CHCl3. [ABSTRACT FROM AUTHOR]