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1.
The reaction of acetylferrocene [Fe(η‐C5H5)(η‐C5H4COCH3)] (1) with (2‐isopropyl‐5‐methylphenoxy) acetic acid hydrazide [CH3C6H3CH(CH3)2OCH2CONHNH2] (2) in refluxing ethanol gives the stable light‐orange–brown Schiff base 1‐[(2‐isopropyl‐5‐methylphenoxy)hydrazono] ethyl ferrocene, [CH3C6H3CH(CH3)2OCH2CONHN?C(CH3)Fe(η‐C5H5)(η‐C5H4)] (3). Complex 3 has been characterized by elemental analysis, IR, 1H NMR and single crystal X‐ray diffraction study. It crystallizes in the monoclinic space group P21/n, with a = 9.6965(15), b = 7.4991(12), c = 29.698(7) Å, β = 99.010(13) °, V = 2132.8(7) Å3, Dcalc = 1.346 Mg m?3; absorption coefficient, 0.729 mm?1. The crystal structure clearly shows the characteristic [N? H···O] hydrogen bonding between the two adjacent molecules of 3. This acts as a bidentale ligand, which, on treatment with [Ru(CO)2Cl2] n, gives a stable bimetallic yellow–orange complex (4). Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
2.
Kohtaro Osakada Yasumasa Takenaka Jun‐Chul Choi Isao Yamaguchi Takakazu Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》2000,38(9):1505-1511
Copolymerization of (4‐hexylphenyl)allene and of (4‐dodecylphenyl)allene with carbon monoxide (1 atm) catalyzed by Rh[η3‐CH(Ar′)C{C(CHAr′)CH2C (CHAr′)CH2CH2CHCHAr′}CH2](PPh3)2 (A; Ar′ = C6H4OMe‐p) gives the corresponding polyketones: I‐[—CO—C(CHAr)—CH2—]n [1: Ar = C6H4C6H13‐p, 2 : Ar = C6H4C12H25‐p; I = CH2C(CHAr′)C(CHAr′)CH2C(CHAr′)CH2CH2CHCHAr′]. Molecular weights of the polyketone prepared from (4‐hexylphenyl)allene and CO are similar to the calculated from the monomer to initiator ratios until the molecular weight reaches to 45,000, indicating the living polymerization. Melting points of the polyketones I‐[—CO—C(CHC6H4R‐p)—CH2—]n (n = ca. 100) increase in the order R = C12H25 < C6H13 < C4H9 < CH3 < H. Block and random copolymerization of phenylallene and (4‐alkylphenyl)allene with carbon monoxide gives the new copoly‐ ketones. The polymerization of a mixture of (4‐methylphenyl)allene and smaller amounts of bis(allenyl)benzene under CO afforded the polyketone with a crosslinked structure. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1505–1511, 2000 相似文献
3.
Synthesis and Characterization of β‐Diketiminate Aluminum Compounds and Their Use in the Ring‐Opening Polymerization of ε‐Caprolactone
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Xiaoli Ma Miaomiao Yao Mingdong Zhong Ziyan Deng Wenling Li Zhi Yang Herbert W. Roesky 《无机化学与普通化学杂志》2017,643(2):198-202
Four aluminum alkyl compounds, [CH{(CH3)CN‐2,4,6‐MeC6H2}2AlMe2] ( 1 ), [CH{(CH3)CN‐2,4,6‐MeC6H2}2AlEt2] ( 2 ), [CH{(CH3)CN‐2‐iPrC6H4}2AlMe2] ( 3 ), and [CH{(CH3)CN‐2‐iPrC6H4}2AlEt2] ( 4 ), bearing β‐diketiminate ligands [CH{(Me)CN‐2,4,6‐MeC6H2}]2 (L1H) and [CH{(Me)CN‐2‐iPrC6H4}]2 (L2H) were obtained from the reactions of trimethylaluminum, triethylaluminum with the corresponding β‐diketiminate, respectively. All compounds were characterized by 1H NMR and 13C NMR spectroscopy, single‐crystal X‐ray structural analysis, and elemental analysis. Compounds 1 – 4 were found to catalyze the ring‐opening polymerization (ROP) of ε‐caprolactone (ε‐CL) with good activity. 相似文献
4.
Cerium‐Complex‐Catalyzed Oxidation of Arylmethanols under Atmospheric Pressure of Dioxygen and Its Mechanism through a Side‐On μ‐Peroxo Dicerium(IV) Complex
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Mitali Paul Satoru Shirase Dr. Yuma Morimoto Dr. Laurent Mathey Dr. Balasubramanian Murugesapandian Dr. Shinji Tanaka Prof. Dr. Shinobu Itoh Prof. Dr. Hayato Tsurugi Prof. Dr. Kazushi Mashima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):4008-4014
A new CeIV complex [Ce{NH(CH2CH2N=CHC6H2‐3,5‐(tBu)2‐2‐O)2}(NO3)2] ( 1 ), bearing a dianionic pentadentate ligand with an N3O2 donor set, has been prepared by treating (NH4)2Ce(NO3)6 with the sodium salt of ligand L1 . Complex 1 in the presence of TEMPO and 4 Å molecular sieves (MS4 A) has been found to serve as a catalyst for the oxidation of arylmethanols using dioxygen as an oxidant. We propose an oxidation mechanism based on the isolation and reactivity study of a trivalent cerium complex [Ce{NH(CH2CH2N=CHC6H2‐3,5‐(tBu)2‐2‐O)2}(NO3)(THF)] ( 2 ), its side‐on μ‐O2 adduct [Ce{NH(CH2CH2N=CHC6H2‐3,5‐(tBu)2‐2‐O)2}(NO3)]2(μ‐η2:η2‐O2) ( 3 ), and the hydroxo‐bridged CeIV complex [Ce{NH(CH2CH2N=CHC6H2‐3,5‐(tBu)2‐2‐O)2}(NO3)]2(μ‐OH)2 ( 4 ) as key intermediates during the catalytic cycle. Complex 2 was synthesized by reduction of 1 with 2,5‐dimethyl‐1,4‐bis(trimethylsilyl)‐1,4‐diazacyclohexadiene. Bubbling O2 into a solution of 2 resulted in formation of the peroxo complex 3 . This provides the first direct evidence for cerium‐catalyzed oxidation of alcohols under an O2 atmosphere. 相似文献
5.
Gopal Chandra Patra Sankar Chandra Bhunia Monoj Kumar Roy Sudhir Chandra Pal 《Helvetica chimica acta》2013,96(1):130-134
Biginelli compounds 1 were first brominated at Me? C(6) with 2,4,4,6‐tetrabromocyclohex‐2,5‐dien‐1‐one to give Br2CH? C(6) derivatives 2 . The hydrolysis of the 6‐(dibromomethyl) group of 2c to give the 6‐formyl derivative 3c in the presence of an expensive Ag salt followed by reaction with N2H4?H2O yielded tetrahydropyrimido[4,5‐d]pyridazine‐2,5(1H,3H)‐dione ( 4c ; Scheme 1). However, treatment of the 6‐(dibromomethyl) derivatives 2 directly with N2H4?H2O led to the fused heterocycles 4 in better overall yield (Schemes 1 and 2; Table). 相似文献
6.
Runqiang Liu Ning Zhao Ping Liu Caixia An Zhaoxun Lian 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(5):451-455
π‐Conjugated organic materials exhibit high and tunable nonlinear optical (NLO) properties, and fast response times. 4′‐Phenyl‐2,2′:6′,2′′‐terpyridine (PTP) is an important N‐heterocyclic ligand involving π‐conjugated systems, however, studies concerning the third‐order NLO properties of terpyridine transition metal complexes are limited. The title binuclear terpyridine CoII complex, bis(μ‐4,4′‐oxydibenzoato)‐κ3O,O′:O′′;κ3O′′:O,O′‐bis[(4′‐phenyl‐2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)cobalt(II)], [Co2(C14H8O5)2(C21H15N3)2], (1), has been synthesized under hydrothermal conditions. In the crystal structure, each CoII cation is surrounded by three N atoms of a PTP ligand and three O atoms, two from a bidentate and one from a symmetry‐related monodentate 4,4′‐oxydibenzoate (ODA2−) ligand, completing a distorted octahedral coordination geometry. Neighbouring [Co(PTP)]2+ units are bridged by ODA2− ligands to form a ring‐like structure. The third‐order nonlinear optical (NLO) properties of (1) and PTP were determined in thin films using the Z‐scan technique. The title compound shows a strong third‐order NLO saturable absorption (SA), while PTP exhibits a third‐order NLO reverse saturable absorption (RSA). The absorptive coefficient β of (1) is −37.3 × 10−7 m W−1, which is larger than that (8.96 × 10−7 m W−1) of PTP. The third‐order NLO susceptibility χ(3) values are calculated as 6.01 × 10−8 e.s.u. for (1) and 1.44 × 10−8 e.s.u. for PTP. 相似文献
7.
Bis(N, N′‐dialkyldithiocarbamato)antimony(III) alkylenedithiophosphates of the type [R2NCS2]2 SbS(S)POGO [where NR2 = N(CH3)2, N(C2H5)2 and N(CH2)4; G = ? CH2? C(C2H5)2? CH2? , ? CH2? C(CH3)2? CH2? , ? CH(CH3)? CH(CH3)? and ? C(CH3)2? C(CH3)2? ] were synthesized and characterized by physico‐chemical, spectral [UV, IR and NMR (1H, 13C and 31P)] and thermal (TG, DTA and DSC) analysis. The TG decomposition analysis step of the complex indicated the formation of Sb2S3 as the final product. The first endothermic peak in DSC indicated the melting point of the complexes. These complexes were screened for their antimicrobial activities using the disk diffusion method. All the complexes showed good activity as antibacterial and antifungal agents on some selected bacterial and fungal strains, which increased on increasing the concentration. Chloroamphenicol and terbinafin were used as standards for comparison. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
8.
Cristiano Zuccaccia Gianfranco Bellachioma Giuseppe Cardaci Alceo Macchioni Barbara Binotti Carla Carfagna 《Helvetica chimica acta》2006,89(8):1524-1546
Palladacyclic compounds [Pd(C6H4(C6H5C?O)C?N? R)(N? N)] [X] (R = Et, iPr, 2,6‐iPr2C6H3; N? N = bpy = 2,2′‐bipyridine, or 1,4‐(o,o′‐dialkylaryl)‐1,4‐diazabuta‐1,3‐dienes; [X]? = [BF4]? or [PF6]?) were synthesized from the dimers [{Pd(C6H4(C6H5C?O)C?N? R)(μ‐Cl)}2] and N? N ligands. Their interionic structure in CD2Cl2 was determined by means of 19F,1H‐HOESY experiments and compared with that in the solid state derived from X‐ray single‐crystal studies. [Pd(C6H4(C6H5C?O)C?N? R)(N? N)] [X] complexes were found to copolymerize CO and p‐methylstyrene affording syndiotactic or isotactic copolymers when bpy or 1,4‐(o,o′‐dimethylaryl)‐1,4‐diazabuta‐1,3‐dienes were used, respectively. The reactions with CO and p‐methylstyrene of the bpy derivatives were investigated. Two intermediates derived from a single and a double insertion of CO into the Pd? C bonds were isolated and completely characterized in solution. 相似文献
9.
Helio G. Bonacorso Rogério V. Lourega Fernando J. Righi Everton D. Deon Nilo Zanatta Marcos A. P. Martins 《Journal of heterocyclic chemistry》2008,45(6):1679-1686
10.
Treatment of the osmabenzene [Os{CHC(PPh3)CHC(PPh3)CH} Cl2(PPh3)2]Cl ( 1 ) with excess 8‐hydroxyquinoline produces monosubstituted osmabenzene [Os{CH C(PPh3) CHC(PPh3)CH}(C9H6NO)Cl(PPh3)]Cl ( 2 ) or disubstituted osmabenzene [Os{CHC(PPh3)CHC(PPh3)CH} (C9H6NO)2]Cl ( 3 ) under different reaction conditions. Osmabenzene 2 evolves into cyclic η2‐allene‐coordinated complex [Os{CH?C(PPh3)CH=(η2‐C?CH2)}(C9H6NO)(PPh3)2]Cl ( 4 ) in the presence of excess PPh3 and NaOH, presumably involving a P? C bond cleavage of the metallacycle. Reaction of 4 with excess 8‐hydroxyquinoline under air affords the SNAr product [(C9H6NO)Os{CHC(PPh3)CHCHC} (C9H6NO)(PPh3)]Cl ( 5 ). Complex 4 is fairly reactive to a nucleophile in the presence of acid, which could react with water to give carbonyl complex [Os{CH?C(PPh3)CH?CH2}(C9H6NO) (CO)(PPh3)2]Cl ( 6 ). Complex 4 also reacts with PPh3 in the presence of acid and results in a transformation to [Os {CHC(PPh3)CHCHC}(C9H6NO)Cl (PPh3)2]Cl ( 7 ) and [Os{CH?C(PPh3) CH=(η2‐C?CH(PPh3))}(C9H6NO) Cl(PPh3)]Cl ( 8 ). Further investigation shows that the ratio of 7 and 8 is highly dependent on the amount of the acid in the reaction. 相似文献
11.
J. R. Wells 《国际化学动力学杂志》2004,36(10):534-544
A bimolecular rate constant,kDHO, of (29 ± 9) × 10?12 cm3 molecule?1 s?1 was measured using the relative rate technique for the reaction of the hydroxyl radical (OH) with 3,5‐dimethyl‐1‐hexyn‐3‐ol (DHO, HC?CC(OH)(CH3)CH2CH(CH3)2) at (297 ± 3) K and 1 atm total pressure. To more clearly define DHO's indoor environment degradation mechanism, the products of the DHO + OH reaction were also investigated. The positively identified DHO/OH reaction products were acetone ((CH3)2C?O), 3‐butyne‐2‐one (3B2O, HC?CC(?O)(CH3)), 2‐methyl‐propanal (2MP, H(O?)CCH(CH3)2), 4‐methyl‐2‐pentanone (MIBK, CH3C(?O)CH2CH(CH3)2), ethanedial (GLY, HC(?O)C(?O)H), 2‐oxopropanal (MGLY, CH3C(?O)C(?O)H), and 2,3‐butanedione (23BD, CH3C(?O)C(?O)CH3). The yields of 3B2O and MIBK from the DHO/OH reaction were (8.4 ± 0.3) and (26 ± 2)%, respectively. The use of derivatizing agents O‐(2,3,4,5,6‐pentalfluorobenzyl)hydroxylamine (PFBHA) and N,O‐bis(trimethylsilyl)trifluoroacetamide (BSTFA) clearly indicated that several other reaction products were formed. The elucidation of these other reaction products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible DHO/OH reaction mechanisms based on previously published volatile organic compound/OH gas‐phase reaction mechanisms. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 534–544, 2004 相似文献
12.
UHMWPE with short‐chain branches synthesized by alkenyl substituted phenoxy–imine catalysts in ethylene polymerization
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Yi Wang Hong Fan Bo‐Geng Li 《Journal of polymer science. Part A, Polymer chemistry》2016,54(24):3808-3818
The alkenyl substituted phenoxy–imine complexes [2‐C3H5‐6‐(2, 3, 5, 6‐C6F4H‐N?CH)C6H3O]2TiCl2 (C3H5=? CH2? CH?CH2 or ? CH?CH? CH3) are synthesized and characterized by 1H NMR, 13C NMR, and elemental analysis. When activated by MAO, they show high activity for the polymerization of ethylene to UHMWPE under different conditions (temperatures and polymerization time). Most of the resulting polymers have high molecular weights (>1.0 × 106 g·mol?1) and high melting points as well as crystallinity. To clarify the effect of the alkenyl group on the catalytic performance and the resultant polymer microstructure, the corresponding saturated complexes of type [2‐C3H7?6‐(2, 3, 5, 6‐C6F4H‐N?CH)C6H3O]2TiCl2 where C3H7 = –CH2? CH2? CH3 or ? CH(CH3)2 were synthesized and tested as catalysts in ethylene polymerization under the same reaction conditions. The microstructure and morphologies of these two species of PE samples were fully compared by the analysis of 13C NMR, GPC, DSC, and SEM. As a result, the allyl substituted complex show the highest activity to prepare the highest molecular weight polyethylene of all the catalysts. An interesting feature of the UHMWPE produced by these four catalysts is that they contain only a few short‐chain branches (mainly methyl, isobutyl and 2‐methylhexyl branches) in a low amount (<2.7 branches/1000 C). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3808–3818 相似文献
13.
Johan K. Terlouw Wigger Heerma John L. Holmes Peter C. Burgers 《Journal of mass spectrometry : JMS》1980,15(11):582-586
The [C4H6O]+˙ ion of structure [CH2?CHCH?CHOH]+˙ (a) is generated by loss of C4H8 from ionized 6,6-dimethyl-2-cyclohexen-1-ol. The heat of formation ΔHf of [CH2?CHCH?CHOH]+˙ was estimated to be 736 kJ mol?1. The isomeric ion [CH2?C(OH)CH?CH2]+˙ (b) was shown to have ΔHf, ? 761 kJ mol?1, 54 kJ mol?1 less than that of its keto analogue [CH3COCH?CH2]+˙. Ion [CH2?C(OH)CH?CH2]+˙ may be generated by loss of C2H4 from ionized hex-1-en-3-one or by loss of C4H8 from ionized 4,4-dimethyl-2-cyclohexen-1-ol. The [C4H6O]+˙ ion generated by loss of C2H4 from ionized 2-cyclohexen-1-ol was shown to consist of a mixture of the above enol ions by comparing the metastable ion and collisional activation mass spectra of [CH2?CHCH?CHOH]+˙ and [CH2?C(OH)CH?CH2]+˙ ions with that of the above daughter ion. It is further concluded that prior to their major fragmentations by loss of CH3˙ and CO, [CH2?CHCH?CHOH]+˙ and [CH2?C(OH)CH?CH2]+˙ do not rearrange to their keto counterparts. The metastable ion and collisional activation characteristics of the isomeric allenic [C4H6O]+˙ ion [CH2?C?CHCH2OH]+˙ are also reported. 相似文献
14.
Murat Aydemir Akın Baysal Nevin Gürbüz İsmail Özdemir Bahattin Gümgüm Saim Özkar Nagihan Çaylak Leyla Tatar Yıldırım 《应用有机金属化学》2010,24(1):17-24
Three new (N‐diphenylphosphino)‐isopropylanilines, having isopropyl substituent at the carbon 2‐ (1) 4‐ (2) or 2,6‐ (3) were prepared from the aminolysis of chlorodiphenylphosphine with 2‐isopropylaniline, 4‐isopropylaniline or 2,6‐diisopropylaniline, respectively, under anaerobic conditions. Oxidation of 1,2 and 3 with aqueous hydrogen peroxide, elemental sulfur or gray selenium gave the corresponding oxides, sulfides and selenides (Ph2P?E)NH? C6H4? 2‐CH(CH3)2, (Ph2P?E)NH? C6H4? 4‐CH(CH3)2 and (Ph2P?E)NH? C6H4? 2,6‐{CH(CH3)2}2, where E = O, S, or Se, respectively. The reaction of [M(cod)Cl2] (M = Pd, Pt; cod = 1,5‐cyclooctadiene) with two equivalents of 1,2 or 3 yields the corresponding monodendate complexes [M((Ph2P)NH? C6H4? 2‐CH(CH3)2)2Cl2], M = Pd 1d, M = Pt 1e, [M((Ph2P)NH? C6H4? 4‐CH(CH3)2)2Cl2], M = Pd 2d, M = Pt 2e and [M((Ph2P)NH? C6H4? 2,6‐(CH(CH3)2)2)2Cl2], M = Pd 3d, M = Pt 3e, respectively. All the compounds were isolated as analytically pure substances and characterized by NMR, IR spectroscopy and elemental analysis. Furthermore, representative solid‐state structure of [(Ph2P?S)NH? C6H4? 4‐CH(CH3)2] (2b) was determined using single crystal X‐ray diffraction technique. The complexes 1d–3d were tested and found to be highly active catalysts in the Suzuki coupling and Heck reaction, affording biphenyls and stilbenes, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
15.
A. Kakanejadifard A. Saniei F. Delfani M. Farnia G. R. Najafi 《Journal of heterocyclic chemistry》2007,44(3):717-718
16.
A Donor‐Stabilized Zwitterionic “Half‐Parent” Phosphasilene and Its Unusual Reactivity towards Small Molecules
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Kerstin Hansen Tibor Szilvási Dr. Burgert Blom Dr. Elisabeth Irran Prof. Dr. Matthias Driess 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(7):1947-1956
The stabilization of the labile, zwitterionic “half‐parent” phosphasilene 4 L′Si?PH (L′=CH[(C?CH2)CMe(NAr)2]; Ar=2,6‐iPr2C6H3) could now be accomplished by coordination with two different donor ligands (4‐dimethylaminopyridine (DMAP) and 1,3,4,5‐tetramethylimidazol‐2‐ylidene), affording the adducts 8 and 9 , respectively. The DMAP‐stabilized zwitterionic “half‐parent” phosphasilene 8 is capable of transferring the elusive parent phosphinidene moiety (:PH) to an unsaturated organic substrate, in analogy to the “free” phosphasilene 4 . Furthermore, compounds 4 and 8 show an unusual reactivity of the Si?P moiety towards small molecules. They are capable of adding dimethylzinc and of activating the S?H bonds in H2S and the N?H bonds in ammonia and several organoamines. Interestingly, the DMAP donor ligand of 8 has the propensity to act as a leaving group at the phosphasilene during the reaction. Accordingly, treatment of 8 with H2S affords, under liberation of DMAP, the unprecedented thiosilanoic phosphane LSi?S(PH2) 16 (L=HC(CMe[2,6‐iPr2C6H3N])2). Compounds 4 and 8 react with ammonia both affording L′Si(NH2)PH2 17 , respectively. In addition, the reaction of 8 with isoproylamine, p‐toluidine, and pentafluorophenylhydrazine lead to the corresponding phosphanylsilanes L′Si(PH2)NHR (R=iPr 18 a ; R=C6H5?CH3 18 b , R=NH(C6F5) 18 c ), respectively. 相似文献
17.
Werner Complexes with ω‐Dimethylaminoalkyl Substituted Ethylenediamine Ligands: Bifunctional Hydrogen‐Bond‐Donor Catalysts for Highly Enantioselective Michael Additions
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M. Sc. Subrata K. Ghosh Dr. Carola Ganzmann Dr. Nattamai Bhuvanesh Prof. Dr. John A. Gladysz 《Angewandte Chemie (International ed. in English)》2016,55(13):4356-4360
The racemic carbonate complex [Co(en)2O2CO]+ Cl? (en=1,2‐ethylenediamine) and (S)‐[H3NCH((CH2)nNHMe2)CH2NH3]3+ 3 Cl? (n=1–4) react (water, charcoal, 100 °C) to give [Co(en)2((S)‐H2NCH((CH2)nNHMe2)CH2NH2)]4+ 4 Cl? ( 3 a – d H4+ 4 Cl?) as a mixture of Λ/Δ diastereomers that separate on chiral‐phase Sephadex columns. These are treated with NaOH/Na+ BArf? (BArf=B(3,5‐C6H3(CF3)2)4) to give lipophilic Λ‐ and Δ‐ 3 a–d 3+ 3 BArf?, which are screened as catalysts (10 mol %) for additions of dialkyl malonates to nitroalkenes. Optimal results are obtained with Λ‐ 3 c 3+ 3 BArf? (CH2Cl2, ?35 °C; 98–82 % yields and 99–93 % ee for six β‐arylnitroethenes). The monofunctional catalysts Λ‐ and Δ‐[Co(en)3]3+ 3 BArf? give enantioselectivities of <10 % ee with equal loadings of Et3N. The crystal structure of Δ‐ 3 a H4+ 4 Cl? provides a starting point for speculation regarding transition‐state assemblies. 相似文献
18.
A series of novel tetraphenylantimony derivatives of exo‐7‐oxa‐bicyclo[2,2,1] heptane (ene)‐3‐arylamide‐2‐acid of the general formula Ph4SbO2CCHCHCH2CH2CH(O)HCONHAr (Ar = Ph,4‐ClC6H4, 4‐BrC6H4, 3‐BrC6H4, 4‐F‐3‐ClC6H3 and 4‐MeC6H4) have been synthesized and characterized by elemental analysis, IR, 1H NMR and mass spectra. The crystal structure of Ph4SbO2CCHCHCH2CH2CH(O)HCONHC6H4CH3·CHCl3 was determined by X‐ray diffraction. Five human neoplastic cell lines (HL‐60, KB, Bel‐7402, BGC‐823 and HCT‐8) were used to screen these compounds. The results indicate that these compounds at 10 µM show certain in vitro antitumor activities. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
19.
Brian L. Mark Jonathan C. Parrish Zhi‐Xian Wang Leonard I. Wiebe Edward E. Knaus Michael N. G. James 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):758-760
This analysis of the title compound, C13H13F2IO3, establishes the orientation of (E)‐5‐(CH=CH—I) as antiperiplanar (ap) to the C—C bond (5–6 position) of the 2,4‐difluorophenyl ring system, with the (E)‐5‐(CH=CH—I) H atom located in close proximity (2.17 Å) to the F4 atom of the 2,4‐difluorophenyl moiety. 相似文献
20.
The absolute bimolecular rate constants for the reactions of C6H5 with 2‐methylpropane, 2,3‐dimethylbutane and 2,3,4‐trimethylpentane have been measured by cavity ringdown spectrometry at temperatures between 290 and 500 K. For 2‐methylpropane, additional measurements were performed with the pulsed laser photolysis/mass spectrometry, extending the temperature range to 972 K. The reactions were found to be dominated by the abstraction of a tertiary C H bond from the molecular reactant, resulting in the production of a tertiary alkyl radical: C6H5 + CH(CH3)3 → C6H6 + t‐C4H9 (1) (1) C6H5 + (CH3)2CHCH(CH3)2 → C6H6 + t‐C6H13 (2) (2) C6H5 + (CH3)2CHCH(CH3)CH(CH3)2 → C6H6 + t‐C8H17 (3) (3) with the following rate constants given in units of cm3 mol−1 s−1: k1 = 10(11.45 ± 0.18) e−(1512 ± 44)/T k2 = 10(11.72 ± 0.15) e−(1007 ± 124)/T k3 = 10(11.83 ± 0.13) e−(428 ± 108)/T © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 645–653, 1999 相似文献