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The title molecules are sought in connection with various synthetic applications. The aliphatic fluorous alcohols R f n CH 2 OH (R f n = CF 3 (CF 2 ) n -1 ; n = 11, 13, 15) are converted to the triflates R f n I (NaI, acetone; 58-69%). Subsequent reactions with NaOCl/HCl give iodine(III) dichlorides R 2 OTf (Tf 2 O, pyridine; 22-61%) and then to R f n CH 2 I (NaI, acetone; 58-69%). Subsequent reactions with NaOCl/HCl give iodine(III) dichlorides R f n CH 2 ICl 2 ( n = 11, 13; 33-81%), which slowly evolve Cl 2 . The ethereal fluorous alcohols CF 3 CF 2 CF 2 O(CF(CF 3 I, are also inert, but additions of TMSCl to bis(trifluoroacetates) R 2 I(OCOCF x CF(CF 3 )CH 2 OH ( x = 2-5) are similarly converted to triflates and then to iodides, but efforts to generate the corresponding dichlorides fail. Substrates lacking a methylene group, R f n I, are also inert, but additions of TMSCl to bis(trifluoroacetates) R f n I, 1,4-R 3 ) 2 appear to generate R f I, and 1,3-R n ICl 2 , which rapidly evolve Cl 2 I are prepared from the corresponding diiodides, copper, and R f6 I (110-130 °C, 50-60%), and afford quite stable R 6 H 4 I, 1,4-R f6 C 6 H 4 I, and 1,3-R f10 C 6 H 4 I are prepared from the corresponding diiodides, copper, and R f n I (110-130 °C, 50-60%), and afford quite stable R f n C 6 H 4 (NIS or I 2 species upon reaction with NaOCl/HCl (80-89%). Iodinations of 1,3-(R f6 ) 2 C 6 H 4 and 1,3-(R f8 CH 2 I and 1,2,4-(R 2 ) 2 C 6 H 4 (NIS or I 2 /H 5 I (77-93%). The former, the crystal structure of which is determined, reacts with Cl 6 ) give 1,3,5-(R f6 ) 2 C 6 H 3 I and 1,2,4-(R f8 CH 2 CH 2 ) 2 C 6 (89%). The relative thermodynamic ease of dichlorination of these and other iodine(I) compounds is probed by DFT calculations.3 I (77-93%). The former, the crystal structure of which is determined, reacts with Cl 2 to give a 75:25 ArICl 2 /ArI mixture, but partial Cl 2 evolution occurs upon work-up. The latter gives the easily isolated dichloride 1,2,4-(R f8 CH 2 CH 2 ) 2 C 6 H 3 ICl 2 (89%). The relative thermodynamic ease of dichlorination of these and other iodine(I) compounds is probed by DFT calculations.

This paper reports the efficient synthesis of the first class of polyisobutylene(PIB)-supported palladium-PEPPSI precatalyst (PEPPSI = pyridine-enhanced precatalyst preparation, stabilization, and initiation). The new complexes are employed in Buchwald-Hartwig amination of aryl chlorides and are found to be reasonably active in the titled cross-coupling reaction. The supported catalysts are tested in polar (1,4-dioxane and 1,2-dimethoxyethane) as well as in aliphatic reaction media (toluene and n-heptane) and display superior activity in the highly lipophilic solvent (n-heptane). The catalytic efficacy of PIB-Pd-PEPPSI precatalyst is measured to be comparable to its nonsupported analog. Pd-leaching is determined by inductively coupled plasma mass spectrometry (ICP-MS) after a simple liquid/liquid extraction and is found to be 2 ppb in the product phase, translating into a recovery of ≈99.8% of the palladium., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A cyclohexanediyl-bridged, bis(N-xylyl) diketiminate ligand, (±)-C6H10(nacnac(Xyl)H)2, LH2 (Xyl = 2,6-dimethylphenyl), was obtained from the reaction of [(2,6-dimethylphenyl)amino]-pent-3-en-2-one first with Meerwein's salt, then with (±)-cyclohexanediamine. The reaction of the ligand with Zr(NMe2)4 yielded LZr(NMe2)2. Protonation of the remaining diamide ligands with EtOH or [H2NMe2]Cl yielded LZr(OEt)2 and LZrCl2, respectively. The latter complex was also obtained by the reaction of LH2 first with nBuLi and then with ZrCl4(THF)2. The dichloride complex yielded LZr(OEt)2 and LZrMe2 upon reaction with NaOEt or MeLi/AlMe3, respectively. X-ray diffraction studies showed a trans-configuration of the ancillary ligands in LZrCl2 and LZrMe2, and a cis-configuration in LZr(NMe2)2 and LZr(OEt)2. LZr(OEt)2 was tested as a catalyst for the polymerization of rac-lactide. Kinetic investigations yielded a rate law first order in catalyst and monomer and a rate constant k = 14(1) L mol(-1) s(-1), the latter being orders of magnitude higher than typical activities for group 4 complexes in lactide polymerization. Analyses of the obtained polymer revealed an atactic polymer and broad polymer molecular weight distributions with sizeable fractions of cyclic oligomers. The influence of contaminants on the polymerization activity was examined: while lactic acid deactivates the catalyst, addition of up to 1 equiv. of water or para-toluenesulfonic acid revitalized catalysts not showing maximum activity.