Diphenylmethane derivatives 1-3, decorated with two guanidine units, are effective catalysts of HPNP transesterification. Substitution of the methylene group of the parent diphenylmethane spacer with cyclohexylidene and adamantylidene moieties enhances catalytic efficency, with gem-dialkyl effect accelerations of 4.5 and 9.1, respectively. Activation parameters and DFT calculations of the rotational barriers around the C-Ar bonds indicate that a major contribution to the driving force for enhanced catalysis is entropic in nature. © 2013 American Chemical Society.
Guanidine–Guanidinium Cooperation in Bifunctional Artificial Phosphodiesterases Based on Diphenylmethane Spacers;gem-Dialkyl Effect on Catalytic Efficiency / Salvio, Riccardo; Mandolini, Luigi; Claudia, Savelli. - In: JOURNAL OF ORGANIC CHEMISTRY. - ISSN 0022-3263. - STAMPA. - 78:14(2013), pp. 7259-7263. [10.1021/jo401085z]
Guanidine–Guanidinium Cooperation in Bifunctional Artificial Phosphodiesterases Based on Diphenylmethane Spacers;gem-Dialkyl Effect on Catalytic Efficiency
SALVIO, RICCARDO;MANDOLINI, Luigi;
2013
Abstract
Diphenylmethane derivatives 1-3, decorated with two guanidine units, are effective catalysts of HPNP transesterification. Substitution of the methylene group of the parent diphenylmethane spacer with cyclohexylidene and adamantylidene moieties enhances catalytic efficency, with gem-dialkyl effect accelerations of 4.5 and 9.1, respectively. Activation parameters and DFT calculations of the rotational barriers around the C-Ar bonds indicate that a major contribution to the driving force for enhanced catalysis is entropic in nature. © 2013 American Chemical Society.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
