Synthesis and Characterization of Lipophilic Organotins. Application to the Functionalization of Silica Gel

Abstract

The synthesis of the lipophilic docosyltri(hex-1-ynyl)tin was achieved in three steps according to two different synthetic pathways. This compound reacted with nonporous silica to yield surface-modified silica via the loss of the three alkynyl functionalities and the formation of Si bulk -O-Sn-C bonds. The reactivity and the maximum chain loading reached were compared to those obtained with the heptadecafluorodecyltin analogue. The differences observed were rationalized in terms of electronic demand and cross-sectional area of the grafted chain, as evidenced by FTIR spectroscopy and X-ray crystal structures of the precursors.

Thermodynamic, Kinetic, Structural, and Computational Studies of the Ph3Sn–H, Ph3Sn–SnPh3, and Ph3Sn–Cr(CO)3C5Me5Bond Dissociation Enthalpies

“… a Cr = Cr­(CO) 3 C 5 Me 5 . Available experimental values determined by X-ray crystallography between brackets. b Taken from ref . c Taken from ref . d This work. e Taken from ref . f Taken from ref . …”

Carbenoid‐Mediated Formation and Activation of Element‐Element and Element–Hydrogen Bonds

“…The molecular structures of both compounds have already been described before. [ 20,21 ] However, Ph 6 Sn 2 was found to crystallize in a different crystal system. The Sn–Sn distances in both molecules of 2.747(1) and 2.776(1) Å differ slightly but are similar compared to those reported earlier.…”

A discrete unsymmetrically substituted dihydrodioxadistannetane with both η1 and intramolecular η2μ2 sulfonate bondings

“…1,3-Dihydro-1,3-dioxa-2,4-distannetanes are usually prepared in two different ways, either by hydrolysis of tin halides or by condensation between a tin oxide or hydroxide and an acid, often under Dean-Stark conditions. During the course of our studies concerning the hydrolysis of organotrialkynyltins [21][22][23][24][25] and bridged organohexaalkynylditins [26][27][28][29] we showed that the use of a bulky substituent on the tin, such as the 2,4,6-trii-propylphenyl group, could allow the isolation of clusters of monoorganotin oxides-hydroxides of various sizes and shapes. When hydrolysis was conducted in the presence of an aromatic sulfonic acid, cationic polysulfonates with three or ten tin atoms and two types of sulfonate bondings, an electrostatic and a bridging one, were isolated [22].…”