Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides ...Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.展开更多
A novel series of para-diiodobenzene derivatives, 3,6-diiodo-4,5-dialkyl-phthalic acid dimethyl esters, were prepared via cycloaddition of two TMS-substituted alkynes and dimethyl acetylenedicarboxylate, which was med...A novel series of para-diiodobenzene derivatives, 3,6-diiodo-4,5-dialkyl-phthalic acid dimethyl esters, were prepared via cycloaddition of two TMS-substituted alkynes and dimethyl acetylenedicarboxylate, which was mediated by zirconocene. After iodination, three new compounds of 3,6-diiodo-4,5-dimethyl（dipropyl, dibutyl）-phthalic acid dimethyl esters （3a, 3b, 3c） were synthesized in high region-selectivity and yields, and characterized by NMR. The crystal structures were determined by single-crystal X-ray diffraction. The crystal of 3a （C12H121204, Mr = 474.02） belongs to the triclinic system, space group Pi with a = 7.6238（10）, b = 9.4571（12）, c = 10.8221（14） A, a = 66.611（10）, fl = 88.511（12）, 7 ： 77.604（11）% V= 697.93（16） A3, Z= 2, F（000） = 444, Dc = 2.256 mg/m3, g = 4.509 mm-1, T=133（2） K, S = 1.014, R = 0.0229 and wR = 0.0547 for 2644 observed reflections with I 〉 20（/）; the crystal of 3b （C16H201204, Mr - 530.12） is of triclinic system, space group Pi with a = 9.4122（19）, b = 10.626（2）, c = 11.353（2） A, a = 97.90（3）, fl = 113.83（3）, y = 110.22（3）°, V= 922.6（3） A3, Z- 2, F（000） = 508, Dc - 1.908 mg/m3, g = 3.422 mm-1, T = 113（2） K, S = 1.115, R = 0.0428 and wR = 0.1072 for 3971 observed reflections with I〉 20（/）; the crystal of 3c （ClsH241204, Mr = 558.17） belongs to the monoclinic system, space group P21/c with a = 26.396（2）, b = 8.7560（8）, c = 25.7970（18） A, fl = 91.721（4）o, V= 5959.6（8） A3, Z = 12, F（000） = 3240, Dc = 1.866 mg/m3,/z = 3.184 mm-l, T= 113（2） K, S = 1.154, R = 0.0424 and wR = 0.0766 for 13056 observed reflections with I 〉 20（/）.展开更多
Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane （MAO） catalyst system under mild condition. High yield was...Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane （MAO） catalyst system under mild condition. High yield was gained and no other oligmer was detected. It was found that the ratio of AI/Zr is responsible for the selectivity of product.展开更多
A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne...A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne and one nitrile mediated by zirconocene. This proposed synthetic method provides a feasible way to the synthesis of large N-heteroeyclic π-conjugated molecules.展开更多
Several supported zirconocene catalysts were prepared by using MgCl_2·6H_2O as a precursor forproducing an active support. Such catalysts combined with methylaluminoxane (MAO) obtained by reactingMgCl_2·6H_2...Several supported zirconocene catalysts were prepared by using MgCl_2·6H_2O as a precursor forproducing an active support. Such catalysts combined with methylaluminoxane (MAO) obtained by reactingMgCl_2·6H_2O with AlMe_3 show good activity for ethylene polymerization similar to that of anhydrousMgCl_2 supported zirconocene catalyst.展开更多
As a discovery of C\_C coupling and amine elimination reaction by treatment of \{6\|dimethylamino\|6\|methylfulvene\} with zirconium tetrachloride, experiments using amino\|substituted benzofulvene 1a or aminopentaful...As a discovery of C\_C coupling and amine elimination reaction by treatment of \{6\|dimethylamino\|6\|methylfulvene\} with zirconium tetrachloride, experiments using amino\|substituted benzofulvene 1a or aminopentafulvene 2a, instead of 6\|dimethylamino\|6\|methylfulvene, gave \{bis\{\[1\|(dimethylamino)\}\}ethenyl\|indenyl\]zirconium dichloride 1c which was characterized by X\|ray diffraction as monoclinic, space group \%C2/c\%, \%a\%=2.028 8(4) nm, \%b\%=0.981 7(2) nm, \%c\%=1.458 9(3) nm, \%β\%=115.73(3)°, \%V\%=2.617 5(9) nm\+3, \%Z\%=4, \%R\%=0.072 3, and bis\[(1\|methyl\|4,5\|dihydro\|2\|pyrrolnyl)cyclopentadienyl\]zirconium dichloride 2c as triclinic, space group \%P\%1, \%a\%=0.807 49(16) nm, \%b\%=\{0.943 40(19)\} nm, \%c\%=\{1.423 8(3)\} nm, \%α\%=91.04(3), \%β\%=97.41(3), \%γ\%=106.68(3)°, \%V\%=1.028 6(4) nm\+3, \%Z\%=2, \%R\%=0.080 0.展开更多
文摘Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.
文摘A novel series of para-diiodobenzene derivatives, 3,6-diiodo-4,5-dialkyl-phthalic acid dimethyl esters, were prepared via cycloaddition of two TMS-substituted alkynes and dimethyl acetylenedicarboxylate, which was mediated by zirconocene. After iodination, three new compounds of 3,6-diiodo-4,5-dimethyl（dipropyl, dibutyl）-phthalic acid dimethyl esters （3a, 3b, 3c） were synthesized in high region-selectivity and yields, and characterized by NMR. The crystal structures were determined by single-crystal X-ray diffraction. The crystal of 3a （C12H121204, Mr = 474.02） belongs to the triclinic system, space group Pi with a = 7.6238（10）, b = 9.4571（12）, c = 10.8221（14） A, a = 66.611（10）, fl = 88.511（12）, 7 ： 77.604（11）% V= 697.93（16） A3, Z= 2, F（000） = 444, Dc = 2.256 mg/m3, g = 4.509 mm-1, T=133（2） K, S = 1.014, R = 0.0229 and wR = 0.0547 for 2644 observed reflections with I 〉 20（/）; the crystal of 3b （C16H201204, Mr - 530.12） is of triclinic system, space group Pi with a = 9.4122（19）, b = 10.626（2）, c = 11.353（2） A, a = 97.90（3）, fl = 113.83（3）, y = 110.22（3）°, V= 922.6（3） A3, Z- 2, F（000） = 508, Dc - 1.908 mg/m3, g = 3.422 mm-1, T = 113（2） K, S = 1.115, R = 0.0428 and wR = 0.1072 for 3971 observed reflections with I〉 20（/）; the crystal of 3c （ClsH241204, Mr = 558.17） belongs to the monoclinic system, space group P21/c with a = 26.396（2）, b = 8.7560（8）, c = 25.7970（18） A, fl = 91.721（4）o, V= 5959.6（8） A3, Z = 12, F（000） = 3240, Dc = 1.866 mg/m3,/z = 3.184 mm-l, T= 113（2） K, S = 1.154, R = 0.0424 and wR = 0.0766 for 13056 observed reflections with I 〉 20（/）.
文摘Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane （MAO） catalyst system under mild condition. High yield was gained and no other oligmer was detected. It was found that the ratio of AI/Zr is responsible for the selectivity of product.
基金Supported by the National Natural Science Foundation of China（No.21102099）.
文摘A series of quinoline derivatives was obtained in high yields by an efficient one-pot reaction of substituted o-diiodobenzenes with azazirconacyelopentadienes, which were conveniently prepared from one internal alkyne and one nitrile mediated by zirconocene. This proposed synthetic method provides a feasible way to the synthesis of large N-heteroeyclic π-conjugated molecules.
文摘Several supported zirconocene catalysts were prepared by using MgCl_2·6H_2O as a precursor forproducing an active support. Such catalysts combined with methylaluminoxane (MAO) obtained by reactingMgCl_2·6H_2O with AlMe_3 show good activity for ethylene polymerization similar to that of anhydrousMgCl_2 supported zirconocene catalyst.
文摘As a discovery of C\_C coupling and amine elimination reaction by treatment of \{6\|dimethylamino\|6\|methylfulvene\} with zirconium tetrachloride, experiments using amino\|substituted benzofulvene 1a or aminopentafulvene 2a, instead of 6\|dimethylamino\|6\|methylfulvene, gave \{bis\{\[1\|(dimethylamino)\}\}ethenyl\|indenyl\]zirconium dichloride 1c which was characterized by X\|ray diffraction as monoclinic, space group \%C2/c\%, \%a\%=2.028 8(4) nm, \%b\%=0.981 7(2) nm, \%c\%=1.458 9(3) nm, \%β\%=115.73(3)°, \%V\%=2.617 5(9) nm\+3, \%Z\%=4, \%R\%=0.072 3, and bis\[(1\|methyl\|4,5\|dihydro\|2\|pyrrolnyl)cyclopentadienyl\]zirconium dichloride 2c as triclinic, space group \%P\%1, \%a\%=0.807 49(16) nm, \%b\%=\{0.943 40(19)\} nm, \%c\%=\{1.423 8(3)\} nm, \%α\%=91.04(3), \%β\%=97.41(3), \%γ\%=106.68(3)°, \%V\%=1.028 6(4) nm\+3, \%Z\%=2, \%R\%=0.080 0.
