Einige Neue N,S-Substituierte 2-Nitrodienverbindungen Aus Reaktionen Von Mono(p-fluorarylthio)substituierten Dienen Mit Aminen

2-Nitrodiene compound 1 was stirred with p-fluorothiophenol for a long time and compound 3 was obtained. Compound 1 gave bis(thio)substituted 2-nitrodiene compound 4 and tris(thio)substituted compound 5 with 2 moles of p-fluorothiophenol in the presence of NaOH in ethanol. The compounds 9a–g have been prepared from 8a–g and 3. Compound 7 was obtained from the reaction of mono(thio)substituted 2-nitrodiene with morpholine. Compound 3 gives 11a–d in the reaction with piperidines in CH₂Cl₂ (or ether). Compound 13a–b have been obtained from the reaction of compound 3 with primary amines 12a–b. Compound 3 gives 15 and 16 in the reaction with 2,5-dimethylpiperazine in CH₂Cl₂.

     

Synthesis,characterization, and reactivity studies in ethylene polymerization of cyclometalated palladium(II) complexes containing terdentate ligands with N,C,N-donors

The reaction of [Na₂PdCl₄] with 3,5-bis(2-pyridoxy)toluene (L_pyH) in acetic acid yields the cyclometalated complex [PdCl(L_py-N, C, N)] (1). Complex 1 can be further converted into neutral species by metathesis reaction exchange of chloride by either iodide or thiocyanate to yield [PdX(L_py-N, C, N)] (X = I (2), SCN (3)). The chloride can be replaced by neutral ligands like pyridine or acetonitrile in the presence of silver tetrafluoroborate to give the corresponding cationic compounds [PdL(L_py-N, C, N)]BF₄ (L = Py (4), MeCN (5)). In contrast, the reaction of [Na₂PdCl₄] with 3,5-bis(3, 5-dimethylpyrazol-1-ylmethyl)toluene (L_pzH) under analogous conditions yields the neutral complex [PdCl₂(L_pzH-N, N)](6) with the ligand bidentate N,N-donor. The cyclometalated palladium complex [PdCl(L_pz-N, C, N)] (7) was prepared by the reaction of Pd(OAc)₂ with L_pzH in acetic acid followed by a metathetic reaction with lithium chloride in acetone/water. Complexes 1, 6, and 7 in the presence of methylaluminoxane (MAO) lead to an active catalyst for the polymerization of ethylene.     

单加成环丙烷富勒烯膦酸酯衍生物的合成与电化学性能

在Mn(OAc)₃•2H₂O催化下, C₆₀分别和亚甲基二膦酸四乙酯、氰基亚甲基膦酸二乙酯或乙氧羰基亚甲基膦酸二乙酯在氯苯中回流, 生成3个单加成环丙烷富勒烯膦酸衍生物C₆₀C(R)PO(OEt)₂ [1, R＝PO(OEt)₂; 2, R＝COOEt; 3, R＝CN]. 与以前报道的Bingel反应法相比, 该方法副产物少并且缩短了反应时间. 采用循环伏安法发现1, 2的还原电位相对于C₆₀发生负移, 而3的还原电位相对于C₆₀却正移40 mV, 表明引入象氰基一样具有很强吸电子能力的取代基团, 可以改善富勒烯球的电化学性能, 合成电子接受能力较强的富勒烯衍生物.     

二茂铁四唑和二茂铁甲醛缩3-取代丙二醇衍生物的合成

以甲酰基二茂铁6为原料, 通过与NH₄OH•HCl的缩合反应得到二茂铁肟7, 再经脱水剂脱水得到二茂铁腈8, 最后在(n-C₄H₉)₃SnCl的作用下与NaN₃反应生成新化合物二茂铁四唑(9). 以甲酰基二茂铁为原料, 在对甲苯磺酸(PTSA)的催化作用下与原甲酸三甲酯反应生成二甲基二茂铁缩醛(10), 然后与(R)-(－)-3-氯-1,2-丙二醇反应得到新的二茂铁缩醛衍生物12, 12再与NaN₃发生取代反应得到新的二茂铁缩醛衍生物13. 而新的二茂铁缩醛衍生物15的合成则是先由(R)-(－)-3-氯-1,2-丙二醇与CH₃OH在NaOH的作用下生成(R)-(－)-1-甲氧基-2,3-丙二醇(14), 再由14与二甲基二茂铁缩醛(10)反应得到的. 所合成的新化合物都用MS, ¹H NMR和IR谱确证了它们的结构.     

EASY LARGE-SCALE SYNTHESIS OF STERICALLY ENCUMBERED 2-IODOBIPHENYLS AND SOME DERIVATIVES THEREOF

The convenient one-pot reaction of o-bromofluorobenzene (1) with n-butyl lithium and aryl Grignard reagents followed by quenching with iodine affords substituted 2-iodobiphenyls (4) in yields of 45 to 71%. Lithiation of 4 followed by reaction with Me₂SiCl₂ affords the silanes ArSiMe₂Cl 7.     

Radical–molecule reaction CH<Subscript>2</Subscript>Cl + NO<Subscript>2</Subscript>: a mechanistic study

The radical–molecule reaction mechanism of CH₂Cl with NO₂ has been explored theoretically at the B3LYP/6–311G(d,p) and MC–QCISD (single-point) levels of theory. Our results indicate that the title reaction proceeds mostly through singlet pathways, less go through triplet pathways. The initial association between CH₂Cl and NO₂ is found to be the carbon-to-nitrogen attack forming the adduct a H₂ClCNO₂ with no barrier, followed by isomerization to b ₁ H₂ClCONO-trans which can easily convert to b ₂ H₂ClCONO-cis. Subsequently, the most feasible pathway is the C–Cl and O–N bonds cleavage along with the N–Cl bond formation of b (b ₁ , b ₂ ) leading to product P ₁ CH₂O + ClNO, which can further dissociate to give P ₅ CH₂O + Cl + NO. The second competitive pathway is the 1,3-H-shift associated with O–N bond rupture of b ₁ to form P ₂ CHClO + HNO. Because the intermediates and transition states involved in the above two favorable channels all lie below the reactants, the CH₂Cl+NO₂ reaction is expected to be rapid, as is confirmed by experiment. The present results can lead us to understand deeply the mechanism of the title reaction and may be helpful for further experimental investigation of the reaction.     

SYNTHESIS OF SOME NEW HETEROCYCLIC COMPOUNDS FROM BENZOPYRANO[2,3-c]PYRAZOL-3-ONE DERIVATIVES

The reaction of benzopyrano[2,3-c]pyrazol-3-one (1) with some active halo compounds, afforded compounds 4, 8 and 12, respectively. The cyanoethyl derivative 19 was synthesized and treated with active methylenes and sulfur or benzoylisothiocyanate and phenacyl bromide, to give compounds 24_a,b and 27. Compounds 25_a,b and 28 were obtained through the reaction of compounds 24_a,b with acrylonitrile or compound 27 with maleic anhydride. Thiation of compound 1 afforded the corresponding thio derivative 29. The reaction of 4-benzylidene-2-methyloxazolin-5-one with compounds 1 or 29 gave products 30_a,b , respectively.     

THE SYNTHESIS,CRYSTAL, MOLECULAR AND ELECTRONIC STRUCTURES OF TRIBROMO(NITROSYL) BIS(TRIPHENYLPHOSPHINE OXIDE) RHENIUM(II) AND TRIBROMO(NITROSYL) BIS(TRIPHENYLPHOSPHINE)RHENIUM(I)

Abstract

Gaseous nitric oxide reacts with a benzene solution of [ReOBr₃(PPh₃)₂] to give [ReBr₃(NO) (OPPh₃)₂] (1). When the reaction is carried out in the presence of an excess of free triphenyl-phosphine, the product is [ReBr₃(NO)(PPh₃)₂] (2). The latter is also isolated in the reaction of 1 with PPh₃. This paper, apart from the synthetic methods, presents spectroscopic and magneto-chemical measurements, and crystal, molecular and electronic structures for 1 and 2.     

New Ni(II) complexes based on N′NN′ pincer ligands: syntheses,structures and B–F cleavage of BF4− promoted by a di-cationic Ni(II) center

A neutral complex [Ni(L1)Cl₂] (1) with trigonal bipyramidal geometry at Ni(II) was prepared by the reaction of NiCl₂ with 2,6-bis(isopropylaminomethyl)pyridine (L1) in THF and then a mono-cationic complex [Ni(L1)Cl](BF₄) (2) and di-cationic complex [Ni(L1)(CH₃CN)₃](BF₄)₂ (3) could be obtained by extracting one or two Cl^? ions from 1 with one or two equivalents of AgBF₄ in THF or acetonitrile, respectively. Similarly, a neutral complex Ni(L2)Cl₂ (4) was formed by reaction of NiCl₂ with 2,6-bis(diethylaminomethyl)pyridine (L2), and the experimental results indicate that Ni(II) of 4 adopts a slightly distorted square pyramidal geometry, which is different from that of 1. Although the reaction of 4 with one equivalent of AgBF₄ resulted in a mono-cationic complex, [Ni(L2)Cl]BF₄ (5), with Ni(II) in a slightly distorted square planar coordination geometry, an unexpected dinuclear Ni(II) complex [Ni(L2-H)(MeOH)F(μ-F)]₂(BF₄)₂ (6) with two fluoride ligands bridging the two Ni(II) centers rather than a di-cationic Ni(II) complex was formed by extracting two Cl^? anions from 4 through the reaction with two equivalents of AgBF₄ in methanol. Complexes 1–6 were characterized by elemental analysis and IR, and structures of 1, 3, 4, 5, and 6 were confirmed by X-ray diffraction analysis.     

The Reactions of Hexachlorocyclotriphosphazatriene with Ligands Including Mercapto Groups

In this work, the reactions of hexachlorocyclotriphosphazatriene (trimer), N ₃ P ₃ Cl ₆ 1, with 2-mercapto-1-methylimidazole (methimazole) 2, 2-mercaptopyrimidine 3, and 2-mercaptopyridine 4 were discussed. Mono- (5) and pentasubstituted (6) phosphazenes were obtained from the reaction of 1 with 2-mercapto-1-methylimidazole. Both mono- (7) and disubstituted geminal (8) phosphazenes were obtained from the reaction of 1 with 2-mercaptopyrimidine. But phoshazene or any phosphorus compound could not be isolated from the reaction of 1 with 2-mercaptopyridine.     

Synthesis and structures of cis -WO2 complexes with 2,3-dihydroxynaphthalene

{Na(OCH₃)[H₃N(CH₂)₂NH₂]₂}[WO₂(C₁₀H₆O₂)₂] (1) was obtained by the reaction of Na₂WO₄ · 2H₂O with 2,3-dihydroxynaphthalene and ethylenediamine. [H₂N(CH₂)₃NH₃]₂[WO₂(C₁₀H₆O₂)₂] (2) was synthesized by the reaction of Na₂WO₄ · 2H₂O with 2,3-dihydroxynaphthalene and 1,3-propylenediamine. Complex 1 was a one-dimensional chain-like structure and the Na atom is in the structure, while complex 2 was a discrete monomer without Na in its structure. The two complexes were synthesized in the same reaction conditions, except that protonated ethylenediamine was used in reaction 1, but 1,3-propylenediamine in reaction 2.     

A NEW AND EFFICIENT SYNTHESIS OF INDENONE

Reaction of dichloroketone 2 with NEt₃ gave indenone (4) in high yield. Catodic reaction of 2 in the presence of C/Pt electrodes afforded the rearranged product 3 in high yield besides a small amount of chlorohydroxyketone 5. Reaction of rearranged dichloroketone 3 with NEt₃ provided indenone (4) as the sole product. The mechanism of these reaction was discussed.     

Construction of Extended and Polymeric 1,3-Dithiolane and Tetrathiafulvalene Derivatives using Cycloaddition of Bun 3P.CS2

Abstract

Cycloaddition of the adduct between Buⁿ ₃P and CS₂ to strained double bonds such as in norbornene gives novel zwitterionic products such as 5. This dissociates to the ylide 4 so that carrying out the reaction in the presence of an aldehyde leads to a Wittig reaction to give 2-alkylidene-1,3-dithiolanes. The compound 5 reacts with acetylenic dipolarophiles by cycloaddition accompanied by loss of Buⁿ ₃P to give dihydro-TTF derivatives. Both these reaction types also occur for norbornadiene and by using this together with dialdehydes or diacetylenes a range of new sulfur-rich extended and polymeric structures have been obtained.     

Synthesis and Characterization of Bimetallic Nickel and Cobalt Carbonyl Complexes Containing Stannyl Groups

The bimetallic NiSn₂ complex Ni(SnBu₃^t)₂(CO)_3, 1, was obtained from the reaction of Ni(COD)₂ and Bu₃^tSnH and CO. The reaction of Co₂(CO)₈ and Bu₃^tSnH afforded the bimetallic Co–Sn complex Co(SnBu₃^t)(CO)₄, 3. Compound 3 was also obtained from the reaction of Co₄(CO)₁₂ and Bu₃^tSnH but in a lower yield. Both compounds 1 and 3 were characterized by single crystal X-ray diffraction, and possess trigonal bipyramidal geometries around the transition metal centre with two and one stannyl ligands, respectively.     

Synthesis and spectroscopic studies of new organotin(IV) complexes with tridentate N- and O-donor Schiff bases

The Schiff bases H₂L¹ and H₂L² have been prepared by the reaction of 2-amino-4-chlorophenol with pyrrole-2-carbaldehyde and 2-hydroxy-1-naphtaldehyde, respectively, and HL³ from reaction of 2-(aminomethyl)pyridine with 2-hydroxy-1-naphtaldehyde. Organotin complexes [SnPh₂(L¹)] (1), [SnPh₂(L²)] (2), [SnMe₂(L²)] (3) and [SnPhCl₂(L³)] (4) were synthesized from reaction of SnPh₂Cl₂ and SnMe₂Cl₂ with these Schiff bases. The synthesized complexes have been investigated by elemental analysis and FT-IR, ¹H NMR and ¹¹⁹Sn NMR spectroscopy. In complexes the Schiff bases are completely deprotonated and coordinated to tin as tridentate ligands via phenolic oxygen, pyrrolic, and imine nitrogens in 1, two phenolic oxygens and imine nitrogen in 2 and 3, and phenolic oxygen, imine and pyridine nitrogens in 4. The coordination number of tin in 1, 2, and 3 is five and in 4 is six.     

LIGAND EXCHANGE AND LIGAND COUPLING VIA THE σ-SULFURANE INTERMEDIATE IN THE REACTION OF ALKYL 2-PYRIDYL SULFOXIDE WITH GRIGNARD REAGENTS: CONVENIENT PREPARATION OF 2,2′-BIPYRIDINES

Abstract

The reaction between methyl 2-pyridyl sulfoxide (1) with Grignard reagents afforded 2,2′-bipyridine (2) in moderate yield. The reaction is considered to involve initial ligand exchange to generate 2-pyridylmagnesium halide which in the subsequent step attacks the original sulfoxide to form the σ-sulfurane that undergoes ligand coupling to afford 2. The reaction of t-butyl 2-pyridyl sulfoxide (3) with C₆H₅MgBr, however, gave only 2-phenylpyridine (4). This may be due to steric hindrance to the initial ligand exchange. Formation of 2 is a convenient process for preparation of 2,2′-bipyridines bearing various substituents.     

1,4-PENTADIEN-3-ONES. A SOURCE FOR SELENANO 1,2,3- SELENA AND THIADIAZOLES

The 4-Selenanols (2,3) and 4-selenanones (4) were obtained by the reaction of 1,4-pentadien-3-ones (1) with sodium hydrogen selenide under different conditions. The fused 1,2,3-selenadiazoles (6) and 1,2,3-thiadiazoles (7) were prepared from 4 on oxidative cyclization with SeO₂ and Hurd–Mori reaction with SOCl₂.     

SYNTHESIS OF FUSED AND SPIRO HETEROCYCLIC COMPOUNDS DERIVED FROM 3,5-PYRAZOLIDINEDIONE DERIVATIVES

Abstract

The reaction of compound 1 with triethyl orthoformate afforded 2, which in turn reacted with CS₂ and active methlyene compounds or malononitrile to give dithiolane and 4-malononitrile methylene derivatives 3,4, respectively. Treatment of compound 4 with active methylene compounds afforded spiro cyclopentene derivatives 5_a-c. Compound 1 was reacted with bromomalononitrile or CS₂ and halocompounds to afford furo-. thieno- and dithiolano-pyrazole derivatives 6–11, respectively. The reaction of compound 12 with phenacyl bromide or benzylidenemalononitrile furnished oxathiol-2-ylidene and pyridinethione derivatives 13,14, respectively. The dibromo derivative 16 was reacted with CS₂ and active methylenes or malononitrile to obtain spiro dithietanes 17a-e and 4-dicyano-methlyene derivative 22, respectively. Compounds 17 underwent a cycloaddition reaction with thioglycolic acid, N-phenylbenzohydrazindoyl bromide, 2,5-dimethylfuran and 1-phenyl-3,5-pyrazolidinedi one to give cycloadducts 18–21, respectively. Treatment of > o-aminothiophenol or o-phenylenediamine with the dicyano compound 22 leads to the formation of spiro thiazepine or spiro diazine derivatives 23_a,b . The arylidene derivatives 24 was reacted with S,S-acetals, N,S-acetals or ammonium dithiocarbamate to afford dithiane, oxazine or pyrazolodithiocarbamate derivatives 25–29, respectively. Chemoselective cyclization of compound 29 with H₂SO₄, NaOH or MeI gave compounds 30–32, respectively. Benzopyrano derivatives 34,36 were obtained through the reaction of compound 1 with a mixture of thiourea, triethyl orthoformate and ethyl cyanoacetate or with cyanoketene S,S diacetals, respectively.     

New acenaphthene-1,2-diimine and its reduction to the tetraanion. Molecular structures of 1,2-bis[(trimethylsilyl)imino]acenaphthene and its lithium derivatives

1,2-Bis[(trimethylsilyl)imino]acenaphthene (1) was synthesized by the reaction of acenaphthenequinone with (Me₃Si)₂NLi in toluene followed by treatment of the reaction product with trimethylchlorosilane. The dianionic derivative [(tms-BIAN)Li₂]₂ (3) was obtained as the final product by reduction of compound 1 with lithium in toluene, whereas reduction in diethyl ether afforded the tetraanion [(tms-BIAN)Li₄(Et₂O)₃]₂ (5). The formation of the paramagnetic mono-and trianions in solution was confirmed by ESR spectroscopy. Compounds 3 and 5 were isolated in the crystalline state and characterized by elemental analysis, IR spectroscopy, and NMR spectroscopy. The crystal structures of 1, 3, and 5 were established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 697–705, April, 2006.     

Regioselective alkylation of the lower rim of p-tert-butylthiacalix[4]arene with N-(p-nitrophenyl)-α-bromoacetamide

The preparation of partially substituted thiacalix[4]arenes 2–6 has been accomplished by conducting the reaction of the thiacalixarene 1 with N-(p-nitrophenyl)-α-bromoacetamide in acetone or acetonitrile in the presence of M₂CO₃ (M = Na, K and Cs). The influence of the reaction conditions (temperature, time, solvent, ratio of the reagents and the nature of the alkali metal carbonate) on regio- and stereoselectivity of this reaction is described.