PHOTOINDUCED ADDITION REACTIONS OF CHLORANIL WITH FURAN DERIVATIVES

Photoinduoed reaction of chloranil (TCBQ) with 2-methylfuran la and 2,5-dimethylfuran 1b in benzene gave addition products 2a and 2b respecvely together with tetrachlorohydroquinone 3. A mechanism of sequential electron and proton transfer from la or 1b to ~3TCBQ followed by coupling of the furfuryl and semiquinone radical pairs was proposed and is evidenced by the photo-CIDNP studies of the TCBQ-1a and TCBQ-1b systems.

Theoretical Study on the Addition Reactions of Benzaldoximes with Propene

The Michael addition reactions of Z and E benzaldoximes with propene were investigated theoretically by DFT method at B3LYP/6-31G^＊ level. The calculation results show that both addition reactions are concerted processes accompanied by the migration of hydrogen from the atom oxygen to carbon. Both products Z and E nitrones have dipolar charge distributions and activities. Z isomer is more favorable in the reaction due to the barrier is lower.

Conjugate Addition Reactions of Functionalized Organozinc-copper Reagents to α,β-Unsaturated Esters

Functionalized organozinc reagents can easily conduct 1,4-addition reaction with unsaturated esters in the presence of Cu(OAc)2 and LiCl under very Anld conditions to give the products in excellent yields.

Ligand Size Effect on PdLn Oxidative Addition with Aryl Bromide： A DFT Study

The process and mechanism of the ligand volume controlled Pd（PR3）2 （PR3=PH3, PMe3, and PtBu3） oxidative addition with aryl bromide were investigated, using density functional theory method with the conductor-like screening model. Association pathway and dissocia-tion pathway were investigated by the comparison of several energies. The cleavage energy of Pd（PR3）2 complex was calculated, as well as the oxidative addition reaction barrier energy of Pd（PR3）n （n=1,2） with aryl bromide in N,N-dimethylformamide solvent. This study proved that the ligands volume possessed a great impact on the mechanism of oxidative addition： less bulky ligand palladium associated with aryl bromide via two donor ligands,but larger bulky ligand palladium coordinated via monoligand.

TDDFT Study on Different Sensing Mechanisms of Similar Cyanide Sensors Based on Michael Addition Reaction

The solvents and substituents of two similar fluorescent sensors for cyanide, 7-diethylamino- 3-formylcoumarin （sensor a） and 7-diethylamino-3-（2-nitrovinyl）coumarin （sensor b）, are proposed to account for their distinct sensing mechanisms and experimental phenomena. The time-dependent density functional theory has been applied to investigate the ground states and the first singlet excited electronic states of the sensor as well as their possible Michael reaction products with cyanide, with a view to monitoring their geometries and photophysieal properties. The theoretical study indicates that the protic water solvent could lead to final Michael addition product of sensor a in the ground state, while the aprotic acetonitrile solvent could lead to carbanion as the final product of sensor b. Furthermore, the Michael reaction product of sensor a has been proved to have a torsion structure in its first singlet excited state. Correspondingly, sensor b also has a torsion structure around the nitrovinyl moiety in its first singlet excited state, while not in its carbanion structure. This could explain the observed strong fluorescence for sensor a and the quenching fluorescence for the sensor b upon the addition of the cyanide anions in the relevant sensing mechanisms.

Guanidinium Lactate Ionic Liquid: An Efficient and Recycling Catalyst for Michael Addition Reaction

A facile and efficient 1, 4-conjungate addition（Michael addition） reaction of active methylene compounds to aft-unsaturated compounds, catalyzed by guanidinium lactate ionic liquid（IL9）, has been developed. A range of chalcones and nitroalkenes together with active methylene compounds have been converted smoothly to the corresponding products in high yields.

Modification of Nano-alumina Surface by Michael Addition Reaction

A general method for modification of nano-alumina surface is investigated using Michael addition reaction with α,β-unsaturated carbonyl compounds.

Tetramethylguanidium Lactate Ionic Liquid: Catalyst-free Medium for Michael Addition Reaction

A catalyst-free, facile and efficient Michael addition reaction of active methylene compounds as well as nitromethane with chalcones catalyzed by guanidinium lactate ionic liquid was done. A series of chalcones, nitromethane, and active methylene compounds were converted smoothly to the corresponding products in high yields. The simple procedure, very mild conditions, high yields, and reuse of the IL without any loss of catalytic activity make this protocol considerably attractive for academic researches and practical applications.

Nickel (Ⅱ) Complex Catalyzed Conjugate Addition Reaction of Functionalised Organozinc Reagents to α,β -Unsaturated Esters

Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in excellent yields.

Addition Reaction of Fe(CO)_n (n = 3～5) on Fullerene C_(50), C_(60), and C_(70): A Density Functional Theory Study

The electronic structure and reactivities of Fe（CO）n （n = 3~5） addition to different fullerenes have been investigated through the first-principles calculations, and the results indicate that Fe（CO）3 and Fe（CO）4 can be adsorbed to the outside network of fullerene via hollow and bridge sites, respectively. Both of them have larger binding energy, but when Fe（CO）5 is adsorbed via the top site, the binding energy is relatively smaller. According to the directional curvature theory, the reactivities of Fe（CO）3 addition to the fullerenes are determined by KM of the ring center, and those of Fe（CO）4 addition by KD of the C–C bond curvature; while for Fe（CO）5, it presents weak reactivities in the addition reaction because of the larger volume effect. No matter whether the addition reaction takes place on the hollow or bridge site, the binding energies show a linear relationship with KD. This work further enriched the directional curvature theory and applied the isolobel analogy theory in the fullerene addition reactions.

CAN TRICHLOROMETHANE SULFONYL BROMIDE BE USED AS AN ADDENDUM AS WELL AS A TELOGEN IN ITS ADDITION REACTION T0 VINYLIDENE FLUORIDE?

CCl_3SO_2Br used as a 'telogen' reacts with CH_2=CF_2 to give mainly the 'mono- adduct' CCl_3CH_2CF_2Br, together with very small amouats of CCl_3CF_2CH_2Br, CCl_2BrCH_2CF_2Br and the 'di-adduct' CCl_3(CH_2CF_2)_2Br. The result indicates that CCl_3SO_2Br can be used as an addendum in trichloromethyl-bromo-addition reactions to olefins.

The Addition Reaction of p-Chlorobenzaldoxime Dehydrodimer with 1,3-Dienes

The addition reaction of p chlorobenzaldoxime dehydrodimer and 1,3 dienes in refluxing chloroform gives linear 1,4 addition products. The reaction is probably a free radical process.

Addition Reaction of Bis(diphenylphosphinyl) Butadiyne with Methylcyclopentadiene

Bis（diphenylphosphinyl）butadiyne reacted with methylcyclopentadiene at room temperature and four isomeric products were obtained. Crystal structures of isomers 1 and 3 have been determined. Crystal data for compound 1 C40H36O2P2·2CHCl3： monoclinic, space group C12/c1 with a = 17.983（2）, b = 11.8723（12）, c = 20.081（2） A, β = 111.218（3）°, V= 3996.5（8） A^3, Z = 4, Mr= 849.36, Dc = 1.412 g/cm^3, F（000） = 1752,μ = 0.546 mm^-1, the final R = 0.0351 and wR = 0.0951 for 3965 observed reflections （I 〉 2σ（I））; and those for compound 3 C40H36O2P2·H2O： triclinic, space group PI with a = 10.4144（15）, b = 13.0558（18）, c = 13.742（2） A, a = 70.453（8）, β = 75.382（8）, γ = 72.312（8）°, V = 1653.7（4） A^3, Z = 2, Mr= 628.64, Dc = 1.262 g/cm^3, F（000） = 664,μ = 0.169 mm^-1, the final R = 0.0593 and wR = 0.1296 for 4891 observed reflections （I 〉 2σ（I））. The structures of the other two isomers are identified via IR, ^1H NMR and MS spectra.

Addition Reactivity of C_(36) Cage Controlled by the Curvature and the Electronic Factors:A DFT Study

The molecular geometries and electronic structures of the fullerene derivatives C36（OH）n（n = 1～2） have been investigated on the basis of density functional theory calculation at the B3LYP/6-31＋＋G＊ level.The geometry optimization results indicate that the location of C2 atom is the most active site in the three potential adding patterns,and the C1 or C2 site has a larger binding energy than C3 for the addition reactions of C36（D6h） cage and OH radicals resulting from the larger curvature.The electronic structure calculation results disclose that the C2 site has larger electronic population in HOMO and larger spin density,and the addition reaction on the C2 site need overcome a lesser energy gap than that on the C1 or C3 site.Thus,the addition is controlled jointly by the curvature and the electronic factors.Besides,when two hydroxyls are added to the C36 surface,the C2 sites are also the most active locations.The most stable addition adduct of C36（OH）2 is the isomer which holds Ci symmetry,and the spin multiplicity seriously affects the stabilities of the adducts.

STUDY ON THE ADDITION REACTION OF 1-IODO-4-CHLOROPERFLOROBUTANE TO 1-HEXENE UNDER REDUCTIVE CONDITIONS

Promoted by various reductants,the addition of 1-iodo-4-chloro- perfluorobutane to 1-hexene giving 1:1 adduct is reported.Based on these facts,several new redox systems are proposed.

Anion cascade reactions Ⅲ:Synthesis of 3-isoquinuclidone bridged polycyclic lactams

Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridged polycyclic lactams from readily available malonamides and 1,4‑dien-3-ones.Various highly substituted bridged polycyclic lactams were synthesized in good to excellent yields by tandem nucleophilic sequences in the presence of t BuOK in commercially available EtOH solvent at 60℃.Notably,the simple reactions can be run on a gram scale.Mechanistically,bis-Michael addition reaction and hemiaminalization reactions are involved in the tandem transformation.

Theoretical study on the synthesis reaction mechanism of trichlorogermyl crylic acid

The synthesis reaction of trichlorogermyl crylic acid has been studied systematically by using quantum chemistry methods for the first time.Geometries of reactants,transition states,and products have been optimized,respectively at the B3LYP/6-311G（d,p） level.Vibrational frequencies,IR intensities and relative energies for various stationary points have been determined.The reaction pathways are identified by intrinsic reaction coordinate（IRC）calculations.Theoretical analysis provided conclusive evidence that the process is completed through five pathways of addition reaction of double bond,and the transition states are found to be four- membered ring compounds.Solvent effects are taken into account with the PCM model at the same level.This preliminary study shows that the complex formation is favored by the use of polar solvent.

Density Functional Theory Studies on the Mechanism of Activation Formic Acid Catalyzed by Transition Metal Oxide MoO

This paper systematically studies the reaction mechanisms of formic acid catalyzed by transition metal oxide MoO. Three different reaction pathways of Routes I, Ⅱ and Ⅲ were found through studying the reaction mechanism of transition metal oxide MoO catalyzing the formic acid. The transition metal oxide MoO interacts with the C=O double bond to form chiral chain compounds（Routes I and Ⅱ） and metallic compound MoOH2（Route Ⅲ）. In this paper, we have studied the mechanisms of two addition reaction pathways and hydrogen abstraction reaction pathway. Routes I and Ⅱ are both addition reactions, and their products are two different chiral compounds MoO3CH2, which are enantiomeric to each other. In Route Ⅲ, metal compounds MoOH2 and CO2 are obtained from the hydrogen abstraction reaction. Among them, the hydrogen abstraction reaction occurring in Route Ⅲ is more likely to occur than the others. By comparing the results of previous studies on the reaction of MxOy-＋ ROH（M= Mo,W; R = Me, Et）, we found that the hydrogen abstraction mechanism is completely different from the mechanism of oxygen-containing organic compound catalyzed by MxOy.

A Facile Synthesis of 0,0-Dialkyl-α-(Phenyl Carbamyloxy) Alkyl Phosphonates

A series of title compounds were synthesized by the addition reaction of dialkyl-α-hydroxyphosphonates and phenyl isocyanate under base catalysis. All new compounds have beenidentified by 1H NMR, 31P NMR, IR and elemental analysis.

Microwave-assisted synthesis of diaryl or aryl-alkyl sulfones without catalyst

The microwave-assisted coupling reaction of electrondeficient aryl halides with sulfinic acid salts through SNAr-based addition reactions within 5-30 min. No catalysts were required under our conditions.