巯甲基二苯甲酮的合成

以NaI为催化剂,以4-溴甲基二苯甲酮或4,4’-二(溴甲基)二苯甲酮为原料,采用硫脲法合成了4-巯甲基二苯甲酮(新化合物,产率75%)或4,4’-二(巯甲基)二苯甲酮(产率83%),其结构经1H NMR,13C NMR,IR和元素分析表征。     

Benzophenone C-glucosides from Polygala telephioides

Three novel benzophenone C-glucosides, 3'-C-beta-D-glucopyranosyl-2',4',6',3-tetrahydroxy-4-methoxybenzophen one, 3'-C-beta-D-glucopyranosyl-2',4',6'-trihydroxy-3,4-dimethoxybenzophen one and 4'-C-beta-D-glucopyranosyl-2',3',5',6',3-pentahydroxybenzophenone, named telephenones A, B, and C were isolated from the whole plant of Polygala telephioides WILLD and their structures determined by analysis of spectroscopic data.     

Co-MCM-41催化氧化二苯甲烷制备二苯甲酮的反应条件

系统地研究了Co掺杂MCM-41用于液相催化氧化二苯甲烷的反应,并探讨了不同溶剂及溶剂用量、反应时间、反应温度、催化剂用量等对二苯甲烷氧化反应的影响;并得出较优的反应条件:m(二苯甲烷)∶m(催化剂)=10∶1;V(二苯甲烷)∶V(冰醋酸)=1∶10;温度为100℃,时间为10 h,二苯甲烷的转化率21%,二苯甲酮的选择性95.8%。     

Heat of formation of Benzophenone Oxide

The heat of formation of benzophenone oxide, Ph₂CO₂, was measured using photoacoustic calorimetry. The enthalpy of the reaction Ph₂CN₂ + O₂ → Ph₂CO₂ + N₂ was found to be ?48.0 ±0.8 kcal mol^?1 and ΔH_f(Ph₂CN₂) was determined by measuring the reaction enthalpy for Ph₂CN₂ + EtOH → Ph₂CHOEt + N₂ (?53.6 ±1.0 kcal mol^?1). Taking ΔH_f(PhCHOEt) = ?10.6 kcal mol^?1 led to ΔH_f(Ph₂CN₂) = 99.2 ± 1.5 kcal mol^?1 and hence to ΔH_f(Ph₂CO₂) = 51.1 ± 2.0 kcal mol^?1. The results imply that the self-reaction of benzophenone oxide i.e., 2Ph₂CO₂ → 2Ph₂CO + O₂ is exothermic by ?76.0 ±4.0 kcal mol^?1.     

Benzophenone photoreduction by heteroatom-containing donors

Nanosecond flash photolysis has been carried out on benzophenone solutions in benzene and acetonitrile in presence of oxygen- and sulfur-containing reductants such as anisole, thioanisole, dibutyl sulfide and methyl 2-octyl ether. The quantum yield of ketyl formation is compared to previous results on the quantum yields of the final benzophenone disappearance. This comparison is also related to previous data on benzophenone reduction by nitrogen-containing reductants such as amines and amides and suggests a general mechanism for benzophenone photoreduction by heteroatom-containing donors.     

大分子二苯甲酮光引发剂的合成及性能研究

合成了两种大分子光引发剂PPI 1和PPI 2,紫外吸收行为均与4-BP相似,摩尔消光系数比4-BP高,且光解速率快。在不加助引发剂EDAB条件下引发单体HDDA聚合效率良好,对比PPI 1和PPI 2,随着吸光基团官能度（分子量）增大,聚合速率增加、最终转化率增高。将各自诱导单体PEGDA聚合的固化膜,在二氯甲烷溶液中浸泡5天后,PPI 1的萃取量是4-BP的44.5%,PPI 2的萃取量是4-BP的40%,说明PPI 1和PPI 2都是引发效率良好的低迁移光引发剂。     

Benzophenone triplet exciplexes with aromatic amines

Conclusions Laser photolysis was used for the direct detection of the spectral and kinetic characteristics of the contact radical-ion pair triplet exciplexes generated upon the interaction of triplet benzophenone with tertiary aromatic amines in nonpolar solvents. The exciplexes disappear as a result of reverse electron transfer and proton transfer.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 928–930, April, 1988.     

Benzophenone/triethylamine-photoinitiated polymerization of methyl acrylate

Benzophenone-sensitized photopolymerization of methyl acrylate was shown to be remarkably enhanced by the addition of small amounts of triethylamine. This was attributed to the efficient formation of an electron-transfer complex between photoactivated benzophenone and ground-state amine. Ketyl and amine free radicals derived from this complex were postulated to be the chain-initiating species. Quantum yield experiments indicated that methyl acrylate itself was also a quencher of the benzophenone triplet state.     

A New Benzophenone from Securidaca inappendiculata

A new benzophenone, securiphenone A was isolated from the roots of Securidaca inappendiculata. Its structure was determined as 2, 3-methylenedioxy-4-methoxybenzophenone by spectroscopic methods.     

Product Selectivity in Semiconductor-Mediated Dehydrazonation of Benzophenone Hydrazone

Secondary amines are obtained in moderate-good yields by reduction of crude imines prepared from N-alkyltriethoxyiminophosphoranes and aldehydes via the aza-Wittig reaction. N-Alkyltriethoxyiminophosphoranes are synthesized by one-pot azidation of alkyl bromides followed by Staudinger reaction.     

一种新型二苯甲酮类光引发剂的合成及其性能研究

本文先以4-甲基二苯甲酮合成4-(溴甲基)二苯甲酮,然后用4-羟基二苯甲酮和4-(溴甲基)二苯甲酮为原材料合成了一种含二苯甲酮结构的新型光引发剂(MBPBP)。通过核磁共振氢谱图确定了其结构;利用紫外吸收谱图研究了其紫外吸收和光降解性能;最后通过RT-FTIR分析了光引发剂浓度、光照强度和反应单体对光聚合反应的影响。结果表明,MBPBP的摩尔消光系数约为二苯甲酮的1.5倍,吸收范围大大增加,延伸到300nm,吸光效率获得大幅提高,光引发活性远大于传统的二苯甲酮,是一种高效光引发剂。     

Selective Electrochemical Aromatic Fluorination of Acetophenone and Benzophenone

Electrochemical fluorination of acetofenone and benzophenone was studied in anhydrous HF and in solutions. The electrochemical fluorination of acetophenone in HF occurred exclusively in the ring and furnished ortho- and meta-isomers of fluoroacetophenone, 2,5-difluoroacetophenone, and 1-(3,3,6,6-tetrafluoro-1,4-cyclohexadienyl)-1-ethanone. The fluorination of benzophenone in anhydrous HF furnished predominantly m-fluorobenzophenone, whereas in the presence of chloroform only chlorination products were obtained. The electrochemical fluorination of acetophenone in acetonitrile gave rise only to mono- and difluorinated products. The reasons for readily occurring oxidative fluorination of aromatic compounds into polyfluoro-1,4-cyclohexadienes were discussed, and the decomposition paths of fluorinated products under electron impact were considered.     

Photoexcited States of UV Absorbers,Benzophenone Derivatives

The UV absorption, phosphorescence and phosphorescence‐excitation spectra of benzophenone (BP) derivatives used as organic UV absorbers have been observed in rigid solutions at 77 K. The triplet–triplet absorption spectra have been observed in acetonitrile at room temperature. The BP derivatives studied are 2,2′,4,4′‐tetrahydroxybenzophenone (BP‐2), 2‐hydroxy‐4‐methoxybenzophenone (BP‐3), 2,2′‐dihydroxy‐4,4′‐dimethoxybenzophenone (BP‐6), 5‐chloro‐2‐hydroxybenzophenone (BP‐7) and 2‐hydroxy‐4‐n‐octyloxybenzophenone (BP‐12). The energy levels and lifetimes of the lowest excited triplet (T₁) states of these BP derivatives were determined from the first peak of phosphorescence. The time‐resolved near‐IR emission spectrum of singlet oxygen generated by photosensitization with BP‐7 was observed in acetonitrile at room temperature. BP‐2, BP‐3, BP‐6 and BP‐12 show photoinduced phosphorescence enhancement in ethanol at 77 K. The possible mechanism of the observed phosphorescence enhancement is discussed. The T₁ states of 2‐hydroxy‐5‐methylbenzophenone, 4‐methoxybenzophenone and 2,4′‐dimethoxybenzophenone have been studied for comparison.     

The Reaction of Triplet State Benzophenone with Acetylacetone

Irradiation of benzophenone in acetic acid containing acetylacetone resulted in regiospecific addition to form cis-2,2-dihpenyl-3-hydroxy-3-methyl-4-acetyloxetane and the rearrangement products therefrom. In the co-presence of copper ions, the regiospecificity is scrambled to give these products and a small amount of 1,1-diphenyl-1-buten-3-one, the secondary decomposition product of the other oxetane arising from the alternative orientation of the addition.     

在聚乙二醇-水体系中合成二苯甲酮

在聚乙二醇-水(PEG-H2O)反应介质中,以Pd(OAc)2为催化剂,通过苯甲酰氯和苯硼酸的偶联反应,高产率地合成了二苯甲酮.与其他有机溶剂体系相比,Pd(OAc)2-H2O-PEG体系催化效率高(转换数(TON)可高达2.5×104),同时,反应条件温和,反应时间短,产率高,不需要使用污染环境严重的膦配体,是制备二苯甲酮的理想绿色催化体系.