The first now named Stille reaction was published 38 years ago, and the last comprehensive revision of this catalysis was in 2004. Since then the knowledge of the different steps of the three possible (and sometimes competing) reaction pathways (cyclic, open, and ionic) has been almost completed by synergistic experimental and theoretical studies: the Stille reaction is perhaps the best characterized catalytic process if we consider the number of intermediates that have been detected. This review concentrates on the mechanistic new knowledge, and on important aspects as the revolution with the use of bulky phosphines, the bimetallic alternative of the Stille reaction, the enantioselectivity in Stille and palladium free Stille processes, the meaning of copper effect, or the possible approaches to make Stille coupling a greener process.

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The air-stable complexes trans- [Ni(C 6 Cl 2 F 3 ) 2 L 2 ] (L = SbPh 3 , 1; AsPh 3 , 2; AsCyPh 2 , 3; AsMePh 2 , 4; PPh 3 , 5) have been synthesized by arylation of [NiBr 2 (dme)] (dme = 1,2-dimethoxyethane) in the presence of the corresponding ligand L (for compounds 1-4) or by ligand substitution starting from 1 (for compound 5). The structures of 1, 2, and 5 have been determined by X-ray diffraction and show an almost perfect square-planar geometry in all cases. Their catalytic activity in insertion polymerization of norbornene have been tested

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A Pd complex, cis-[Pd(C F ) (THF) ] (1), is proposed as a useful touchstone for direct and simple experimental measurement of the relative ability of ancillary ligands to induce C-C coupling. Interestingly, 1 is also a good alternative to other precatalysts used to produce Pd L. Complex 1 ranks the coupling ability of some popular ligands in the order P Bu >o-TolPEWO-F≈tBuXPhos>P(C F ) ≈PhPEWO-F>P(o-Tol) ≈THF≈tBuBrettPhos≫Xantphos≈PhPEWO-H≫PPh according to their initial coupling rates, whereas their efficiency, depending on competitive hydrolysis, is ranked tBuXPhos≈P Bu ≈o-TolPEWO-F>PhPEWO-F>P(C F ) ≫tBuBrettPhos>THF≈P(o-Tol) >Xantphos>PhPEWO-H≫PPh . This "meter" also detects some other possible virtues or complications of ligands such as tBuXPhos or tBuBrettPhos.

A new generation of porous polymer networks has been obtained in quantitative yield by reacting two rigid trifunctional aromatic monomers (1,3,5-triphenylbenzene and triptycene) with two ketones having electron-withdrawing groups (trifluoroacetophenone and isatin) in superacidic media. The resulting amorphous networks are microporous materials, with moderate Brunauer-Emmett-Teller surface areas (from 580 to 790 m g), and have high thermal stability. In particular, isatin yields networks with a very high narrow microporosity contribution, 82% for triptycene and 64% for 1,3,5-triphenylbenzene. The existence of favorable interactions between lactams and CO molecules has been stated. The materials show excellent CO uptakes (up to 207 mg g at 0 °C/1 bar) and can be regenerated by vacuum, without heating. Under postcombustion conditions, their CO/N selectivities are comparable to those of other organic porous networks. Because of the easily scalable synthetic method and their favorable characteristics, these materials are very promising as industrial adsorbents.

The behavior in CDCl3 of complexes of the type [M(C6F5)X(OPPy n Ph3 - n )] (M = Pd, Pt; X = C6F5; halide; n = 1−3) has been studied by 19F and 1H NMR spectroscopy. For the nonplanar N,N-chelating ligands with n = 2, 3, two processes have been observed and their activation parameters, ΔG ⧧, ΔH ⧧, and ΔS ⧧, have been determined, using magnetization transfer (MT) or line-shape analysis methods. The rotation of the C6F5 groups about the M−Cipso bond occurs in the square-planar species without dissociation, and its rate depends on the size of the coordinated atom X, in the order C6F5 > Cl > Br > I. The rotation for the last three is very slow and is detected only by MT. With OPPy3 the occurrence of associative exchange of free and coordinated Py groups is observed (studied only for X = C6F5, Cl), the rate depending on M and X in the order Pd > Pt and Cl > C6F5. Only for [Pd(C6F5)Cl(OPPy3)] is this rate faster than the C6F5 rotation, producing the effect of an apparent rotation with anomalously low activation parameters. The structures of two complexes, [Pd(C6F5)Br(OPPy2Ph)] and [Pd(C6F5)2(OPPy2Ph)], have been studied by X-ray diffraction.

A detailed study of the Negishi cross-coupling reaction of ArI (Ar = 2-C 6 H 4 CO 2 Et) and ZnEt 2 with palladium catalysts containing conventional phosphines versus one using a chelating hybrid phosphine−electron-withdrawing olefin (P-EWO) ligand reveals that for conventional phosphines (e.g., PPh 3 ) β-H elimination from intermediate [PdArEt(PPh 3 ) 2 ] is competitive with Ar−Et reductive elimination and is responsible for part of the undesired reduction product ArH. In contrast, with the EWO phosphine, the β-H elimination from intermediate [PdArEt(P-EWO)] is slow compared to the fast Ar−Et reductive elimination, and the undesired reduction product ArH observed proceeds in this case of hydrolysis of ZnArEt, formed in transmetalations where Ar is transferred from Pd to Zn. The rate of these transmetalations is comparable to the rate of reductive eliminations. Consequently, undesired transmetalations affording [PdEt 2 (P-EWO)] and ZnArEt are more effective at early stages of the reactions and less effective when the ethylating agent becomes poorer in ZnEt 2 and richer in ZnEtX (X = I), as the reaction proceeds. Careful analysis of the experiments reveals the detailed changing evolution of the reaction, not only providing the main features of the catalytic cycle but also deducing how the reagents in the system change with time and what the effects on the products of these changes are.