Photo-promoted carbonylation of chloroalkanes with carbon monoxide by non-precious metal catalysts

The photo-promoted carbonylation of chloroalkanes with carbon monoxide was carried out under ambient conditions with copper and cadmium salts catalysts. The results indicated that the corresponding esters were produced with three salt catalysts, i.e.CuBr2, CuCl2 and CdI2. Among these catalysts, CdI2 was the most efficient in terms of ester yield and selectivity, particularly, 60% yield and 75% selectivity in the carbonylation of chlorocyclohexane were achieved. Furthermore, the yield and selectivity of the ester can be improved greatly by adding tri-n-butylamine in the CuBr2 and CuCl2 catalyst systems. On the other hand, the additive. As a result, we suggest that iodide ion plays an important role in the catalyst system of the cadmium salts.

Photopromoted Carbonylation of Alkyl Bromides Catalyzed by Copper Salts under Ambient Conditions

Photopromoted carbonylation of alkyl bromides with carbon monoxide or carbon dioxide catalyzed by copper salts can be carried out under ambient conditions （atmospheric pressure and room temperature） and the corresponding ester was produced. The yield and the selectivity of the ester can be improved greatly by addition of sodium phosphate.

Partially crystallized Pd nanoparticles decorated TiO_2 prepared by atmospheric-pressure cold plasma and its enhanced photocatalytic performance

TiO2 decorated with partially crystallized Pd nanoparticles （Pd/TiO2-P） was successfully prepared by atmospheric-pressure dielectric barrier discharge cold plasma. The XRD and XPS analyses proved that Pd ions were reduced to partially crystallized metallic Pd nanoparticles in Pd/TiO2-P. The XPS spectra also indicated that an enhanced metal-support interaction was formed due to the existence of partially crystallized Pd nanoparticles with lower coordination number in Pd/TiO2-P. Photocatalytic activity of Pd/TiO2-P was much higher than that of TiO2 samples decorated with well crystallized Pd nanoparticles.

Photopromoted methoxycarbonylation of olefin with methyl formate by Co(OAc)2

The photopromoted methoxycarbonylation of olefin with methyl formate catalyzed by Co（OAc）2 at ambient conditions has been carried out. The results indicated that the reaction activity increased with the increasing temperature. Methyl formate decomposed into CO and CH3OH firstly under irradiation, and then the methoxycarbonylation of olefin proceeded under catalysis of Co（OAc）2. The mechanism of methyl formate participating in the methoxycarbonylation is verified by the IR analysis and the labeling experiments of CDHOD and CH3^18OH.

Cobalt-catalyzed photopromoted carbonylation of chloroalkanes in the presence of KI

The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the catalytic activity of Co（OAc）2 was higher than that of CoCl2.A basic additive NaOAc was beneficial to the reaction.Interestingly,with NaOAc as an additive, Co（OAc）2 and CoCl2 exhibited similar catalytic activity.Preliminary work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation.

Photopromoted carbonylation of bromobenzene under ambient conditions

The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.

Photopromoted carbonylation of 1-bromo-6-chlorohexane under ambient conditions

Photopromoted carbonylation of 1-bromo-6-chlorohexane with CO catalyzed by CuBr2 and CdI2 has been carried out under ambient conditions. The results indicate that the carbonylation proceeds with the major product of chloroester ClCH2（CH2）5COOCH3 under catalysis of CuBr2. Furthermore, the activity of the carbonylation can be improved by addition of basic additives （NaOAc, Na3PO4 or （n-C4H9）3N）. Among these additives, （n-C4H9）3N is the most efficient in terms of the yield of ClCH2（CH2）5COOCH3. However, the methoxycarbonyl substituting chlorine product of BrCH2（CH2）5COOCH3 is not obtained in the presence of CdI2. This is quite different from the carbonylation of monochloroalkane.

Syntheses,Crystal Structures and Characterization of Two Zeotype Crystals of K_4Cr_3O(H_2O)_3(OOCH)_6]_2[P_2W_(18)O_(62)]·9.5H_2O and K_4[Cr_3O(H_2O)_3(OOCH)_6]· [H_3P_2W_(17) Co(H_2O)O_(61)·20H_2O

Two novel zeotype crystals, K4[Cr30（H2O） 3（OOCH） 6] 2[ P2W18O62]· 9.5H2 O and K4[ Cr3O（ H2O）3（ OOCH）6 ]2[ H3 P2 W17Co（H2O） O61]· 20H2O（2） , were synthesized and their structures were determined using X-ray single crystal diffraction. Crystal data： C12H43O103.5K4Cr6P2W18（1）, hexagonal P6（3）/m, α= 1. 5895（2） nm, b=1.5895（2） nm, c =2.1620（4） nm, α=90°, β=90°, γ= 120°, V=4.7305（13） nm^3, Z=2, R1 =0,0726, ωR2 =0. 1542; C6H57O98K4Cr3CoP2W17 （2）, hexagonal P6（3）/mmc, α = 1.61328（3） nm, b = 1.61328（3） nm, c=2.06613（9） nm, α=90°, β=90°, γ=120°, V=4.6570（2） nm^3, Z=2, R1 =0.0377, ωR2 =0. 1070. These crystals were characterized using elemental analysis, IR, TG-DTA, and XRD. It was found that the polyoxometalate anions maintained Wells-Dawson structure for crystal I and laeunary Wens-Dawson structure for crystal 2. Thermal analysis showed that crystal 1 lost the water of crystallization at 132 ℃, whereas crystal 2 lost the water of crystallization at 100 ℃. Crystal 1 could reversibly desorb and adsorb water molecules and its crystal structure could be restored after re-adsorbing the water molecules. It was also found from the XRD patterns that the void size of crystal 2 is smaller compared with that of crystal 1, which is attributed to the higher anion charges.

The carbonylation of phenyl bromide and its derivatives under visible light irradiation

The carbonylation of phenyl bromide catalyzed by Co（OAc）_2 has been investigated with PhCOPh as a sensitizer under visible light in the presence of basic additive.With strong base CH_3ONa,PhCOOCH_3 is produced in 70%yield with 100%selectivity,the similar results are also obtained with a stronger base（CH_3）_3CONa.However,with another strong base NaOH,the yield of the ester is only 40%.On the other hand,with weak base NaOAc or（n-C_4H_9）_3N,phenyl bromide cannot be carbonylated.The results of carbonylation of the six substituted phenyl bromides suggest that the activities of o,m,p-BrC_6H_4CH_3 are similar to phenyl bromide, while the activities of o,m,p-BrC_6H_4Cl are higher with the high yields（≥93%） of the corresponding chloro-esters.In addition,the relative position of bromine and chlorine or methyl on phenyl ring has little effect on the activity of the carbonylation.