Reaction Of 3c Research Articles

Heterodinuclear Diphosphane-Bridged Iron–Platinum Diyne Complexes as Metalloligands for the Assembly of Polymetallic Systems (Fe, Pt, Co)

Treatment of [(OC)3Fe(μ-C=O)(µ-dppm)Pt(PPh3)] (1a) (dppm=Ph2PCH2PPh2) with 1,7-octadiyne affords the isomeric dimetallacyclopentenones [(OC)2Fe(µ-dppm)(µ-C(=O)C{(CH2)4C≡CH}=CH)Pt(PPh3)] (2a) and [(OC)2Fe(µ-dppm)(µ-C(=O)C(H)=C{(CH2)4C≡CH})Pt(PPh3)] (2a′). In a similar manner, the reaction with 1,3-diethynylbenzene and 1,4-diethynylbenzene yields [(OC)2Fe(μ-C(=O)C{C6H4–C≡CH}=CH)(μ-dppm)Pt(PPh3)] (2b,c); using [(OC)3Fe(μ-C=O)(µ-dppa)Pt(PPh3)] (1b) (dppa=Ph2PNHPPh2) as starting material provides [(OC)2Fe(μ-C(=O)C{p-C6H4–C≡CH}=CH)(μ-dppa)Pt(PPh3)] (2d). The isomeric μ-vinylidene complexes [(OC)3Fe(µ-dppm){(µ-C=CH(C6H4C≡CH)})Pt(PPh3)] (3b,c) result from treatment of [(OC)3Fe{Si(OMe)3}(μ-dppm)Pt(H)(PPh3)] with the two aromatic diynes. Reaction of 2a with a further equivalent of 1a yields the structurally characterized tetranuclear species [(OC)2Fe(µ-dppm)(µ-C(=O)C{(CH2)2}=CH)Pt(PPh3)]2 (4a). A dissymmetric heterotetranuclear dimetallacyclopentenone 4b is produced by reacting 2b with [(OC)3Fe(μ-C=O)(µ-dppa)Pt(PPh3)] (1b). An unusual heterotetranuclear dimetallacyclopentenone-μ-vinylidene compound 4c results from reaction of 3c with 1 equivalent of 1a. The dimetallacyclopentenone-dicobaltatetrahedrane cluster [(OC)2Fe(µ-dppm)(µ-C(=O)C{(CH2)4(η2-HC2Co2(CO)6}=CH)Pt(PPh3)] (5a) is formed by addition of [Co2(CO)8] to 2a. Likewise, [(OC)2Fe(µ-dppm)(µ-C(=O)C{C6H4(η2-HC2Co2(CO)4(µ-dppm)}=CH)Pt(PPh3)] (5b) is produced by mixing [Co2(CO)6(µ2-dppm)] with 2b. When attempting to prepare a heterotetranuclear complex by reacting 2a with [Co2(CO)6{P(OPh)3}2], the targeted compound was not formed. Instead, the substitution product [(OC)2Fe(µ-dppm)(µ-C(=O)C{(CH2)4C≡CH}=CH)Pt{P(OPh)3}] (6a) was isolated. 2b reacts in an analogous manner yielding [(OC)2Fe(μ-C(=O)C{C6H4–C≡CH}=CH)(μ-dppm)Pt{P(OPh)3}] (6b).

Heterobimetallic Metal–Amidinate Complexes by Stepwise Metalation of Methanetrisamidines

AbstractThe acidity of the four N–H groups in methanetrisamidine 1c differs significantly, thereby allowing stepwise metalation by metal organic compounds such as ZnMe2, AlMe3, and GaMe3. Dinuclear complexes 3a–c were formed under kinetic control in the reactions of 1c with 2 equiv. of the metal organic compounds at low temperatures, whereas prolonged reaction times at elevated temperature (100 °C) with 4 equiv. of ZnMe2, AlMe3, and GaMe3 yielded the corresponding tetranuclear complexes 4a–c. The different acidity of the four N–H groups also allowed the stepwise metalation of 1c by two different metal organic complexes with the formation of the heterobimetallic complexes 5a and 5b. In addition, transmetalation by Zn/Al exchange was observed in the reaction of 3c with AlMe3, yielding the corresponding dinuclear aluminium complex 3a. The complexes were characterized by NMR and IR spectroscopy and single‐crystal X‐ray diffraction (3a, 4b, 5a).

Reactions of (1,3,3-Trichloro-2,2,4,4-tetramethylcyclobutyl)sulfenyl Chloride with Some S- and O-Nucleophiles

The sterically crowded 3,3-trichloro-2,2,4,4-tetramethylcyclobutanethione (2c) easily reacts with phosphorus pentachloride in CCl4 yielding the relatively stable (1,3,3-trichloro-2,2,4,4-tetramethylcyclobutyl)sulfenyl chloride (3c). The reactions of 3c with benzylsulfane (4) and thiocamphor (5) occur with elimination of HCl leading to the unsymmetrical disulfanes 6 and 9. In the case of the sulfenates 10 and 12, which are formed as intermediates in the reactions of 3c with propargyl and allyl alcohol, respectively, the subsequent [2,3]-sigmatropic rearrangement yields the corresponding sulfoxides 11 and 13.

Aryldimethylsilyl Modified Hypersilanes

AbstractAryldimethylsilyl‐substituted hypersilanes ArSiMe2Hyp [Hyp =Si(SiMe3)3; Ar = Mes (3a), Bph (3b), Mph (3c), Pph (3d), Tph (3e); Dpp (3f); with Mes = 2,4,6‐Me3C6H2, Bph = 2‐PhC6H4, Mph = 2‐MesC6H4, Pph = 2′,3′,4′,5′,6′‐pentamethylbiphenyl2‐yl, Tph = 2′,4′,6′‐triisopropylbiphenyl‐2‐yl and Dpp = 2,6‐Ph2C6H3] have been synthesized by a multi‐step reaction starting from the readily available starting materials ArI and (thf)xKHyp. For this purpose the aryl iodides were first converted into the lithium aryls by lithium‐halogen exchange with n‐butyl lithium. A salt‐metathesis reaction with SiMe2Cl2 gave the corresponding arylchlorodimethylsilanes (2a–e) in excellent yields. Finally, reaction of 2a–e with (thf)xKHyp afforded the hypersilanes 3a–e in yields up to 86 %. Bis(aryldimethylsilyl)‐substituted silanes (ArSiMe2)2Si(SiMe3)2 (Ar = Mph (4c), Tph (4e)) were obtained by the reaction of 3c or 3e with KOtBu and the corresponding chlorosilanes 2c or 2e. All new compounds have been characterized by melting point, elemental analysis, 1H, 13C, and 29Si NMR spectroscopy and for selected species by IR spectroscopy or mass spectrometry. In addition, the solid‐state structures of silanes 3a–d, 3f, and 4c have been investigated by single crystal X‐ray diffraction.

Studies on 4‐Thiazolidinones: Scope of the Reactions of 3‐Aryl‐2‐thioxo‐1,3‐thiazolidin‐4‐ones with Cyanide and Cyanate Ions

AbstractTreatment of 3‐aryl‐2‐thioxo‐1,3‐thiazolidin‐4‐ones 1 with CN− and NCO− effected the ring cleavage providing [(cyanocarbonothioyl)amino]benzenes 4 and arylisothiocyanates 5, respectively. Similar treatment of 5‐(2‐aryl‐2‐oxoethyl) derivatives 2 afforded 2,4‐bis(2‐aryl‐2‐oxoethylidene)cyclobutane‐1,3‐diones 6 along with each of the preceding products. Treatment of the respective (E,Z)‐5‐(2‐aryl‐2‐oxoethylidene) analogues 3b and 3c with CN− gave 4b and 4c and 2‐(arylcarbonyl)‐2‐methoxy‐4‐oxopentanedinitriles 7b and 7c, in addition to 3,6‐bis[2‐(4‐chlorophenyl)‐1‐methoxy‐2‐oxoethylidene]‐1,4‐dithiane‐2,5‐dione 8c, which has been generated from 3c. Reactions of 3c or 3d with NCO− provided 5c or 5d, together with 8c or 8d as pure isomers. In the formation of the MeO products 7 and 8, the solvent (MeOH) has participated. Structures of these products are based on microanalytical and spectroscopic data. Rationalizations for the above transformations are given.

Eine einfache Synthese von 1,3-Dihydro-1,3-diborapentafulven-Derivaten / A Convenient Synthesis of 1,3-Dihydro-1,3-diborapentafulvene Derivatives

Reaction of 3,3-dimethyl-1-butynyllithiumwith boron trichloride followed by hydroboration with HBCl2 leads to 1,1-bis(dichloroboryl)-3,3-dimethylbutene (4a). Halogen exchange with boron triiodide yields the corresponding tetraiodide 4b, which undergoes a redox reaction with 3-hexyne to give the 1,3-dihydro-1,3-diborapentafulvene 3b. Its 1,3-dimethyl derivative 3c is less stable and rearranges to nido-C4B2 carboranes as well as to polymeric products. Hydroboration of 3c with HBEt2 results in the formation of the nido-C3B3 carborane 6c. The reaction of 3c with Mo(CO)6 yields the 1,3-diborapentafulvene complex 7c.

ChemInform Abstract: Nucleophilic Substitution in Some 5-Chloropyrimidines. Synthesis and Properties of Condensed Pyridopyrimidines.

Abstract Reaction of hetarylacetonitriles 1 with 5-chloro-2-(methylsulfonyl)-4-pyrimidinecarbonyl chloride affords a series of new ketonitriles 3e – h . The reactions of compounds 3 with aliphatic amines were studied. In the reaction of 3c , d , g with aliphatic amines the replacement of methylsulfonyl group took place to give products 4 . In the reaction of 3a with aliphatic amines 3-NR 1 R 2 -5-oxo-5 H -pyrimido-[4,5-c]quinolizin-6-yl cyanides 5a – d were formed. Compounds 3 cyclized into fused pyridopyrimidines 6 – 10 in the presence of Et 3 N and the displacement of methylsulfonyl group in 6 , 7 , 9 by amines was investigated.

Nucleophilic Substitution in Some 5-Chloropyrimidines. Synthesis and Properties of Condensed Pyridopyrimidines

Reaction of hetarylacetonitriles 1 with 5-chloro-2-(methylsulfonyl)-4-pyrimidinecarbonyl chloride affords a series of new ketonitriles 3e– h. The reactions of compounds 3 with aliphatic amines were studied. In the reaction of 3c, d, g with aliphatic amines the replacement of methylsulfonyl group took place to give products 4. In the reaction of 3a with aliphatic amines 3-NR 1R 2-5-oxo-5 H-pyrimido-[4,5-c]quinolizin-6-yl cyanides 5a– d were formed. Compounds 3 cyclized into fused pyridopyrimidines 6– 10 in the presence of Et 3N and the displacement of methylsulfonyl group in 6, 7, 9 by amines was investigated.

Synthesis and Reactivities of Cationic Diruthenium Complexes with Terminal Vinylidene Ligands. Hydration and Novel Cyclization of Acetylenes on the Diruthenium Center

The cationic diruthenium complexes with a terminal vinylidene ligand [Cp*RuCl(μ2-SPri)2Ru(CCHR)Cp*][OTf] (3a, R = COOMe; 3b, R = COMe; 3c, R = H; Cp* = η5-C5Me5, OTf = OSO2CF3) were obtained in high yields by the reaction of [Cp*RuCl(μ2-SPri)2Ru(OH2)Cp*][OTf] with HC⋮CR. Hydration of 3a and 3b gave the carbonyl complex [Cp*RuCl(μ2-SPri)2Ru(CO)Cp*][OTf] and CH3R in almost quantitative yields, while the reaction of 3c with water gave the μ2-acetyl complex [Cp*RuCl(μ2-SPri)2{μ2-C(O)Me}RuCp*][OTf] (5). A reaction mechanism for the former reactions is proposed, which includes hydration of the vinylidene ligands to form the μ2-β-ketoacetyl complexes with a six-membered dimetallacyclic structure [Cp*Ru(μ2-SPri)2(η1:η1-μ2-COCH2COR‘)RuCp*]+ (R‘ = OMe, Me) and the following decarbonylation reaction of the μ2-COCH2COR‘ ligand on the bimetallic center to produce the carbonyl complex and CH3COR‘ via the enolato−carbonyl complexes [Cp*Ru(CO)(μ2-SPri)2Ru(OCR‘CH2)Cp*]+. In accordance with this mechanism, the reaction of 3a with MeOH afforded [Cp*Ru(μ2-SPri)2{η1:η1-μ2-C(OMe)CHCOOMe}RuCp*][OTf] (7). Complexes 3a and 3b reacted with p-tolylacetylene to form the dinuclear metallacyclic complexes 9a and 9b [Cp*Ru(μ2-SPri)2{η1:η1-μ2-C(Tol)CCCHC(R‘)O}RuCp*][OTf] (9a, R‘ = OMe; 9b, R‘ = Me), respectively. The structures of 3b, 5, 7, and 9a have been determined by X-ray crystallography.

Iminophosphane und Azadiphosphiridin‐imine

Iminophosphanes and Azadiphosphiridine IminesA variety of bis(alkyl)iminophosphanes R—PN—R' 3a—e (R = CMe2Et, CMeEt2, CEt3; R' = CMe3, CEt3) and arylimine‐substitued derivatives [R' = 2,4,6‐tBu3C6H2, R = CEt3 (3f), R = PhCHCH (3g)] are obtained by base‐induced dehydrochlorination from the corresponding amino(chloro)phosphanes R—P(Cl)—N(H)R' 2a—g. Depending on the steric demand of the substituents, the iminophosphanes 3a—d undergo a reversible [2 + 1] cyclodimerization to give the azadiphosphiridine imines R—P(NR')—P(R)—N—R' 4a—d. The same ring system is obtained in the reaction of 3c with the (arylimino)‐phosphanes R—PN—aryl (R = PhCHCH, Et, Me). However, this cycloaddition results in the formation of diastereomers 4e—g and 4'e—g, respectively. The reaction of Et—PN—aryl with R—PN—aryl (R = PhCHCH, Cl) furnishes (phosphanylamino)iminophosphanes Et(R)P—N(aryl)—PNaryl 5a, b. The compounds 3f, 4e, f, and 5a have been characterized by X‐ray structure analyses.

A novel synthesis of 2‐vinylindoles and their utilization in the diels‐alder reaction for the formation of new [c] annellated carbazole derivatives

AbstractA facile synthesis of 2‐vinylindoles is detailed, starting from the corresponding indolecarbinols. The utility of the newly synthesized 2‐vinylindoles in the preparation of novel [c] annellated carbazoles is demonstrated. 1‐(1‐Methyl‐2‐indolyl)‐1‐(N‐methyl‐2′‐pyrrolyl)ethene (3c) has also a 2‐vinylpyrrole partial structure. However, in the Diels‐Alder reaction of 3c, the exclusive formation of [c] annellated indoles was observed.