Diallyl Derivatives Research Articles

Ferrocenyl carborane conjugates with allyl functionalities: Synthesis and properties

A series of novel hybride ferrocene carborane derivatives containing allyl functionalities at the carborane carbon atoms were firstly synthesized in a good yield providing their potential applications in various fields of material science. Synthesized compounds were characterized using various spectroscopic techniques like IR, ESI-MS, 1H and 11B NMR data. Some compounds were investigated by cyclic voltammetry. The total charge density around each atom was calculated for 1-allyl-9-ferrocenylmethyl-m-carborane. Particular attention has been focused on the analysis of 1H NMR spectra of diallyl-substituted ferrocene carboranes which made it possible to discover the migration of the double bond in allyl substituent and the formation along with diallyl derivative of the corresponding allylpropenyl isomer compounds.

Synthesis of Carbazole Alkaloids by Ring‐Closing Metathesis and Ring Rearrangement–Aromatization

AbstractAprocess for the assembly of carbazole alkaloids has been developed on the basis of ring‐closing metathesis (RCM) and ringrearrangement–aromatization (RRA) as the key steps. This method is based on allyl Grignard addition to isatin derivatives to provide smooth access to 2,2‐diallyl 3‐oxindole derivatives through a 1,2‐allyl shift. The diallyl derivatives were used as RCM precursors to afford a novel class of spirocyclopentene‐3‐oxindole derivatives, which underwent a novel RRA reaction to afford carbazole derivatives. The synthetic sequence to carbazoles was shortened by combining the RCM and RRA steps in an orthogonal tandem catalytic process. The utility of this methodology was further demonstrated by the straightforward synthesis of carbazole alkaloids, including amukonal derivative, girinimbilol, heptaphylline, and bis(2‐hydroxy‐3‐methylcarbazole).

Synthesis of Carbazole Alkaloids by Ring‐Closing Metathesis and Ring Rearrangement–Aromatization

Aprocess for the assembly of carbazole alkaloids has been developed on the basis of ring-closing metathesis (RCM) and ringrearrangement-aromatization (RRA) as the key steps. This method is based on allyl Grignard addition to isatin derivatives to provide smooth access to 2,2-diallyl 3-oxindole derivatives through a 1,2-allyl shift. The diallyl derivatives were used as RCM precursors to afford a novel class of spirocyclopentene-3-oxindole derivatives, which underwent a novel RRA reaction to afford carbazole derivatives. The synthetic sequence to carbazoles was shortened by combining the RCM and RRA steps in an orthogonal tandem catalytic process. The utility of this methodology was further demonstrated by the straightforward synthesis of carbazole alkaloids, including amukonal derivative, girinimbilol, heptaphylline, and bis(2-hydroxy-3-methylcarbazole).

Synthesis and resolution of diastereomers of (R,R)-1,2-cyclohexylenediamino-di-phenylmethylphosphonates

Salen-like compounds, such as bis-aminophosphonic systems bearing a (R,R)-1,2-diamino-cyclohexyl (DACH) moiety, were synthesized by the addition of dialkyl phosphites to the azomethine bond of N,N′-dibenzylidene-1,2-diaminocyclohexane 2. Five bis-aminophosphonates, dimethyl, diethyl, diisopropyl, dibenzyl, and diallyl derivatives, were obtained in high diastereoselectivity. Three of these compounds, dimethyl 3a, diethyl 3b, and diisopropyl 3c derivatives, had the predominant diastereoisomers separated. A hypothetical explanation of the diastereoselectivity is also reported.

Microwave-assisted N-allylation of uracil and thymine pyrimidine bases

This work presents a new synthetic approach to N(1)-allylation of pyrimidine nucleobases with allyl bromide. The increased efficiency of the proposed method is based on two specific elements: (a) the nucleoside N-deprotonation is carried out in a homogeneous system by using sodium methylsulfinyl- methylide in DMSO; (b) the allylation reaction is microwave-assisted. This method ensures high yields (87–88%) of the monoallylated products and short reaction time (1.5 h as compared to tens of hours for classical methods), and provides protection against side reactions. NMR analysis of the crude reaction mixture indicated a ratio of 6–8 : 1 between N(1)-allyl derivatives and N(1),N(3)-diallyl derivatives.

Novel lupane triterpenoids containing allyl substituents in ring A: synthesis and in vitro study of antiinflammatory and cytotoxic properties

Selective methods for the synthesis of C(2)-monoallyl and C(2)-diallyl derivatives of lupane terpenoids were developed. The methods involve reactions of allyl halides with potassium enolates or potassium enoxy(triethyl)borates generated in situ from 3-oxolupanes (betulonic acid, 3-oxo betulin) under the action of KN(SiMe3)2, KH, or ButOK with subsequent addition of Et3B. The use of the reagent KN(SiMe3)2-Et3B in 1,2-dimethoxyethane ensured the kinetically controlled generation of enolate anions, which yielded 2β-propenyl lupane terpenoids with high stereoselectivity. Reactions of 3-oxolupanes with excesses of ButOK and allyl halide (2.5 equiv.) gave 2,2-bisallylation products. In vitro studies revealed that one of the latter efficiently suppresses the NO production by activated macrophages and has an antitumor effect on Ehrlich carcinoma and P-815 mastocytoma cell lines.

Design and Synthesis of 1‐Benzazepine Derivatives by Strategic Utilization of Suzuki–Miyaura Cross‐Coupling, Aza‐Claisen Rearrangement and Ring‐Closing Metathesis

AbstractA new and simple methodology has been realized for the synthesis of 7‐substituted 2,3,4,5‐tetrahydro‐1‐benzazepine derivatives with Suzuki–Miyaura cross‐coupling, aza‐Claisen rearrangement and ring‐closing metathesis (RCM) the key steps. Here, o‐allylacetanilide derivatives were obtained by Suzuki–Miyaura cross‐coupling of the corresponding o‐iodoacetanilides. The o‐allylacetanilides, on N‐allylation under phase‐transfter catalysis conditions, provided diallyl derivatives as suitable precursors for RCM. These diallyl derivatives, on treatment with Grubbs' second‐generation catalyst, gave the 1‐benzazepine derivatives in moderate‐to‐good yields. These RCM products were found to be unstable and so they were hydrogenated to provide stable tetahydro‐1‐benzazepine derivatives 25–28. 1H‐1‐Benzazepin‐2‐one derivatives 44 and 45 were synthesized following a similar sequence. In addition, the aza‐Claisen rearrangement was utilized as a key step in the preparation of RCM precursor 17. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Formation of Arenes via Diallylarenes: Strategic Utilization of Suzuki–Miyaura Cross‐Coupling, Claisen Rearrangement and Ring‐Closing Metathesis

AbstractTwo new synthetic strategies for benzoannulation are reported. The first strategy is based on the Suzuki–Miyaura cross‐coupling reaction. To this end, various ortho‐diallylbenzene derivatives were prepared from the corrresponding diiodo derivatives by an allylation strategy using an allylboronate as coupling partner. These diallyl derivatives were subjected to a ring‐closing metathesis (RCM) and one‐pot dichlorodicyanoquinone (DDQ) oxidation sequence to deliver 2‐substituted naphthalenes. In the second strategy, a double Claisen rearrangement and RCM protocol have been used as key steps to give highly functionalized benzoannulated quinone derivatives.

Synthesis of cholaphanes by ring closing metathesis

The synthesis of cholaphanes by ring closing metathesis (RCM) of 3α,7α,12α,24-tetraol allyl derivatives, obtained from cholic acid, was attempted. The reactions of tetraol 3,24-diallyl ether or 3,24-diacrylate were not satisfactory. However, diallyl derivatives of disteroidal 3,3′- or 24,24′- ortho-phthalates reacted smoothly affording cyclic dimers in good yields. In all the reactions studied, the E isomers of the macrocycles were obtained in excess.

Synthesis of Spirocycles via Ring Closing Metathesis of Heterocycles Carrying gem‐Diallyl Substituents Obtained via Ring Opening of (Halomethyl)cyclopropanes with Allyltributyltin.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of spirocycles via ring closing metathesis of heterocycles carrying gem-diallyl substituents obtained via ring opening of (halomethyl)cyclopropanes with allyltributyltin.

In the presence of allyl tri-n-butyltin--AIBN, cyclopropylmethyl bromides/xanthates undergo ring-opening reaction with concomitant formation of geminal diallyl derivatives in good yields. The ring closing metathesis reactions on geminal diallyl derivatives with Grubbs' catalyst provided spirocyclopentenyl products. Combination of these two methodologies has been applied to the synthesis of mono-, bis-cyclopentyl-carbohydrates as well as spirocyclopentylproline derivatives.

ChemInform Abstract: A Novel Route to Preussomerins via 2-Arylacetal Anions.

Dimerization of salicylaldehydes provided 6H,12H-6,12-epoxydibenzo[b,f][1,5]dioxocins in multigram quantities. Deprotonation−allylation of the benzylic acetals followed by further functionalization of the diallyl derivative and double Friedel−Crafts cyclization gave a novel preussomerin analogue which possessed the full carbon skeleton of the natural products.

A novel route to preussomerins via 2-arylacetal anions.

[reaction--see text] Dimerization of salicylaldehydes provided 6H,12H-6,12-epoxydibenzo[b, f][1,5]dioxocins in multigram quantities. Deprotonation-allylation of the benzylic acetals followed by further functionalization of the diallyl derivative and double Friedel-Crafts cyclization gave a novel preussomerin analogue which possessed the full carbon skeleton of the natural products.

Synthesis and evaluation of a copolymeric chiral stationary phase

A copolymer based on a broadly applicable chiral selector has been synthesized by hydrosilylation of an enantiopure diallyl derivative of 4-(3,5-dinitrobenzamido)-3-propyl-1,2,3,4-tetrahydrophenanthrene with a difunctional oligomethylhydrosiloxane. The linear copolymer has alternating selector–oligomer units, providing a well-defined strand. The spacing between the chiral units is controlled by the length of the oligomethylhydrosiloxane units. This new chiral stationary phase shows improved chromatographic performance relative to its brush-type and sidechain-modified polysiloxane analogs, as evidenced by data obtained by high-performance liquid and supercritical fluid chromatography. The copolymeric CSP affords increased enantioselectivity under cryogenic conditions and loses little chromatographic efficiency at optimized flow-rates under these conditions.

Aryloxy complexes and cyclometallated aryloxy alkylidene complexes of tungsten (VI). Application to the metathesis of functionalized olefins

In this review article, the synthesis of aryloxy complexes of tungsten with the general formula W(OAr) x Cl 6− x is described together with that of aryloxy (chloro)neopentylidene-tungsten complexes. The properties of these compounds in the metathesis of non-functionalized and functionalized olefins are reviewed. The aryloxy complexes of tungsten are good air-stable precursor catalysts when combined with organotin or -lead cocatalysts. In particular, depending on the cocatalyst and substituents on the aryloxide ligands, one can achieve either linear or cross-linked polydicyclopentadienes. One can also govern the induction period for the obtention of cross-linked polydicyclopentadiene, a phenomenon compatible with the requirements of the RIM processing. The cyclometallated neopentylidene tungsten complex 1 can be synthesized by two different routes, either from the W(OAr) 2Cl 4 (OAr = -O-2,6-C 6H 3Cl 2 or -O-2,6-C 6H 3Ph 2) precursor or from the Schrock carbyne W(CCMe 3)(Cl 3)(dme). In both cases, when OAr = O-2,6-C 6H 3Ph 2, a metallation occurs by cleavage of the CH bond in one substituting phenyl group. Complex 1 is probably one of the most active and stereoselective catalysts for metathesis of cis- and trans-2-pentene (total retention of the configuration of the starting olefin). Similarly, it selectively transforms 1-methyl-norbornene to 100% cis, 100% headtail syndiotactic poly-1-methyl-norbornene. Complex 1 is also one of the most active catalysts for metathesis of functionalized olefins: with ethyl oleate 1 converts approximatively 250 equivalents of ethyl oleate into 9-octadecene and diethyl-9-octadecenedioate at 25°C. Compound 1 converts approximatively 100 equivalents of unsubstituted diallyl ether into the corresponding 2,5-dihydrofurane, and it (as well as the bicomponent catalysts) is able to realize metathesis of ω-unsaturated glucosides into the corresponding di-glucosides. It is also able to convert cyclic and acyclic double bonds with thio-ether functionalities to the corresponding polymer or cyclic products. For example, 1 converts diallyl sulphide or related compounds to the corresponding 2,5-dihydrothiophene derivatives. Similarly, phosphorus, silicon and tin diallyl derivatives can be transformed into the corresponding cyclic compound ECH 2CHCHC H 2, E = P, Si, Sn.

Synthesis of telechelic dienes from fluorinated α,ω-diiodoalkanes. Part I. Divinyl and diallyl derivatives from model I(C 2F 4) nI compounds

The synthesis of five fluorinated non-conjugated dienes from commercially available α,ω-diiodoperfluoroalkanes is described. Preparation of the fluorinated divinyl derivatives H 2C=CH(CF 2) n CH=CH 2 ( n = 2, 4, 6) ( 2,2, 2,4 and 2,6) was effected by ethylenation of these diiodinated compounds in various ways followed by dehydroiodination in ethanolic potassium hydroxide. Allyl diolefines, H 2C=CHCH 2(CF 2) n CH 2CH=CH 2 ( 4,4 and 4,6) were produced by the α,ω-bis-telomerization of allyl acetate followed by deiodoacetoxylation in the presence of zinc. The diacetate precursors 3,4 and 3,6 of the respective diallyls 4,4 and 4,6 were obtained rather than diacetate 3,2 because of the eventual decomposition of α,ω-diiodoperfluoroethane by β-scission. These five fluorinated non-conjugated dienes have been characterized by 1H, 13C and 19F NMR spectroscopy.

Studies on the Synthesis of Polyarylates with Allylic Side Groups. Part 1. Polyarylates from 2,2-bis (3-allyl-4-hydroxyphenyl)propane and Isophthaloyl Chloride

Conditions of synthesis of diallyl derivatives of bisphenol-A via a Claisen rearrangement reaction and the preparation of polyarylates from these derivatives via interfacial polycondensation with isophthaloyl chloride were established. The structure of polymers was confirmed by the methods of 1H-NMR, IR, and UV/Vis spectroscopy and elementary analysis. The results of intrinsic viscosity determinations and thermal analysis revealed the high molecular weight and considerable thermal resistance of these polyarylates.

Studies on the Synthesis of Polyarylates with Allylic Side Groups. Part 1. Polyarylates from 2,2-bis (3-allyl-4-hydroxyphenyl)propane and Isophthaloyl Chloride

Conditions of synthesis of diallyl derivatives of bisphenol-A via a Claisen rearrangement reaction and the preparation of polyarylates from these derivatives via interfacial polycondensation with isophthaloyl chloride were established. The structure of polymers was confirmed by the methods of 1H-NMR, IR, and UV/Vis spectroscopy and elementary analysis. The results of intrinsic viscosity determinations and thermal analysis revealed the high molecular weight and considerable thermal resistance of these polyarylates.

ChemInform Abstract: Formation of Benzo Thia Crowns (II), (III) in the Reaction of the Diallyl Derivative (I) of 2‐Mercapto‐4‐methylphenol with SCl2.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Unexpectedly rapid hydrosilation polymerization of the diallyl derivative of bisphenol A and 2,6-diallylphenol

Abstract : Several members of a novel family of reactive oligomers and polymers have been synthesized using the hydrosilation polyaddition of 1,1,3,3- tetramethyldisiloxane and 1,1,3,3,5,5-hexamethyltrisiloxane with the 2,2'- diallyl derivative of bisphenol A (BPA) or 2,6-diallylphenol. Polymerization occurred much faster than that observed for any other hydrosilation reaction of which we are aware: while a typical hydrosilation takes minutes to hours to complete with catalytic amounts of various platinum catalysts, and most unprotected functional groups inhibit the addition, reactions of 2-allylphenol moieties occur virtually instantaneously. In fact, reactions of the diallyl monomers listed must be cooled to prevent explosive loss of reagents from the reaction vessel; even then, thermal loss of the silane monomers can disrupt stoichiometric balance. With cooling, good yields of polymers were obtained which possess excellent solubility in virtually all organic solvents and intrinsic viscosity values of 0.21-0.23 dL/g.