Cinnamyl Bromide Research Articles

Self-Assembly of a Hierarchical Metal-Organic Framework at the Liquid/Liquid Interface via π-π Stacking Manipulations in Organoplatinum(IV) Complexes for Methanol Fuel Cells.

This study focuses on the facile synthesis of the hierarchical architecture of zeolitic imidazolate framework-8 (ZIF-8) films containing an ultrasmall amount of Pt(0) by investigating the synthesis of different organoplatinum complexes and manipulating the π-π stacking effect in these complexes at the liquid/liquid interface. The organometallic Pt(IV) precursors were complexes with a formula of [PtXMe2(R)(bpy)] (bpy = 2,2'-bipyridine; for complex 2, R = CH2CH═CHC6H5 and X = Br; for complex 3, R = CH2CH═CH2 and X = Br; for complex 4, R = Me and X = I) prepared by oxidative addition of cinnamyl bromide, allyl bromide, or methyl iodide to [PtMe2(bpy)] (complex 1). Different thin films were synthesized starting from three organometallic Pt(IV) precursors (i) by reduction of the Pt complexes at the toluene/water interface (TF2-TF4), (ii) by encapsulation of the Pt precursors in a ZIF-8 (TF5-TF7), and (iii) by reduction of the Pt precursors onto a ZIF-8 (TF8-TF10). The self-assembly of ZIF-8 and different organoplatinum precursors at the interface of two immiscible liquids leads to the preparation of films with well-engineered structures such as rhombic dodecahedra, nanorods, hierarchical architectures, and nanowires, which are very difficult and complicated to synthesize under normal conditions. The ultralow loading of platinum complexes with different degrees of π-π stacking of dangling moieties has a great impact on the structure and morphology (directing agent), which in turn drastically changes the catalytic properties. The obtained films were applied as electrocatalysts for methanol oxidation in fuel cells. The electrocatalytic performance of organoplatinum containing a cinnamyl group in hierarchical architecture TF8 was found to be superior to those of nonhierarchical structures.

Facile synthesis of homoallylamines via α-regioselectivity in ultrasonic mediation and γ-adduct syn-stereoselective allylation with AlCl3-catalysis

The allylation reaction of aldimines with allyl metal reagents is an important synthetic method for the preparation of homoallylamines. Therefore, we wish to report a highly regioselective and stereoselective allylation reaction under sonochemical Barbier-type reaction conditions. The high yields of regioselective α-adducts were achieved by reacting cinnamyl bromide, zinc, 1,2-dibromoethane, and aldimine in THF under sonochemical Barbier-type conditions. Highly regioselective and stereoselective allylation reactions were also achieved under Lewis acid-promoted Barbier-type reaction conditions.

Recyclable Silica-Support Taniaphos/Copper(Ⅰ) complex for asymmetric allylic alkylation reactions

The first immobilization of recyclable Taniaphos/copper(Ⅰ) complex on a commercial accessible silica by thiol-ene coupling reaction has been achieved. The immobilization strategy and linker length are found to have significant impact on catalyst selectivities. Furthermore, we have realized the first heterogeneous asymmetric allylic alkylation reactions involving organometallic reagents using this catalyst system, and three types of cinnamyl bromide substrates are found to be suitable with up to 95% enantioselectivity and 96% yield. Notably, the catalyst shows good stability and cyclicity after five recycles without loss of selectivity and the products can be easily isolated with > 95% purity without chromatography purification.

Cross-coupling of Cinnamyl Bromides and Alkyl Boronates Catalyzed by a Pd-Fe MOF

Cross-coupling of Cinnamyl Bromides and Alkyl Boronates Catalyzed by a Pd-Fe MOF

Synthesis and Pharmacological Evaluation of Enantiopure N-Substituted Ortho-c Oxide-Bridged 5-Phenylmorphans.

The design of enantiopure stereoisomers of N-2-phenylcyclopropylmethyl-substituted ortho-c oxide-bridged phenylmorphans, the E and Z isomers of an N-cinnamyl moiety, and N-propyl enantiomers were based on combining the most potent oxide-bridged phenylmorphan (the ortho-c isomer) with the most potent N-substituent that we previously found with a 5-(3-hydroxy)phenylmorphan (i.e., N-2-phenylcyclopropyl methyl moieties, N-cinnamyl, and N-propyl substituents). The synthesis of the eight enantiopure N-2-phenylcyclopropylmethyl ortho-c oxide-bridged phenylmorphans and six additional enantiomers of the N-substituted ortho-c oxide-bridged phenylmorphans (N-E and Z-cinnamyl compounds, and N-propyl compounds) was accomplished. The synthesis started from common intermediates (3R,6aS,11aS)-10-methoxy-1,3,4,5,6,11a-hexahydro-2H-3,6a-methano-benzofuro[2,3-c]azocine (+)-6 and its enantiomer, (3S, 6aR, 11aR)-(-)-6, respectively. The enantiomers of ±-6 were obtained through salt formation with (S)-(+)- and (R)-(-)-p-methylmandelic acid, and the absolute configuration of the (R)-(-)-p-methylmandelate salt of (3S, 6aR, 11aR)-(-)-6 was determined by single-crystal X-ray analysis. The enantiomeric secondary amines were reacted with N-(2-phenylcyclopropyl)methyl derivatives, 2-(E)-cinnamyl bromide, and (Z)-3-phenylacrylic acid. These products led to all of the desired N-derivatives of the ortho-c oxide-bridged phenylmorphans. Their opioid receptor binding affinity was measured. The compounds with MOR affinity < 50 nM were examined for their functional activity in the forskolin-induced cAMP accumulation assay. Only the enantiomer of the N-phenethyl ortho-c oxide-bridged phenylmorphan ((-)-1), and only the (3S,6aR,11aR)-2-(((1S,2S)-2-phenylcyclopropyl)methyl)-1,3,4,5,6,11a-hexahydro-2H-3,6a-methanobenzofuro[2,3-c]azocin-10-ol isomer ((+)-17), and the N-phenylpropyl derivative ((-)-25) had opioid binding affinity < 50 nM. Both (-)-1 and (-)-25 were partial agonists in the cAMP assay, with the former showing high potency and low efficacy, and the latter with lower potency and less efficacy. Most interesting was the N-2-phenylcyclopropylmethyl (3S,6aR,11aR)-2-(1S,2S)-enantiomer ((+)-17). That compound had good MOR binding affinity (Ki = 11.9 nM) and was found to have naltrexone-like potency as a MOR antagonist (IC50 = 6.92 nM).

Bromine Radical Catalysis by Energy Transfer Photosensitization.

We report here a mild, safe, and user-friendly bromine radical catalysis system that enables efficient [3 + 2] cycloaddition of diversely substituted vinyl- and ethynylcyclopropanes with a broad range of alkenes, including drug-like molecules and pharmaceuticals. Key to the success is the use of photosensitizing triplet-state β-fragmentation of a judiciously selected precatalyst, cinnamyl bromide, to generate bromine radicals in a controlled manner using parts per million-level photocatalyst (i.e., 4CzIPN) loading.

Lead-Mediated Highly Diastereoselective Allylation of Aldehydes with Cyclic Allylic Halides.

Lead was found to efficiently mediate the allylation reactions of carbonyl compounds with cyclic allylic halides in the presence of stoichiometric amounts of lithium chloride and a catalytic amount of GaCl3 (20 mol %), leading to the desired homoallylic alcohols in modest to high yields with excellent diastereocontrol (>99:1 syn/anti) and good functional group tolerance. In contrast, the use of either 2-pyridinecarboxaldehyde as the carbonyl substrate or ( E)-cinnamyl bromide as the allylating agent produced the corresponding product with reversed diastereoselectivity (>99:1 anti/syn).

Bismuth‐Mediated Diastereoselective Allylation Reaction of Carbonyl Compounds with Cyclic Allylic Halides or Cinnamyl Halide

AbstractAn efficient diastereoselective allylation of various carbonyl compounds with cyclic allylic halides by using commercially available bismuth powder in the presence of LiI was developed. Among all the metals screened, bismuth was found to be the best mediator for the transformation. The reactions involving various cyclic allylic halides proceeded smoothly at room temperature to produce the desired homoallylic alcohols in good to excellent yields with high diastereoselectivities (&gt;99:1 dr). Reversed diastereoselectivity was obtained when carbonyl substrate (e. g., 2‐pyridinecarboxaldehyde, glyoxylic acid) containing chelating substituent was used in the allylation reaction. In addition, the reactions involving acyclic (E)‐cinnamyl bromide as substrate worked equally well with high diastereocontrol.magnified image

Synthesis of Thieno-Fused Five- and Six-Membered Nitrogen and Oxygen Heterocycles via Intramolecular Heteroannulation of 4,5-Substituted 3-Amino or 3-Hydroxy 2-Functionalized Thiophenes.

Diverse general high-yield routes for novel thieno-fused five- and six-membered nitrogen and oxygen heterocycles such as thieno[3,2-b]pyrroles, thieno[3,2-b]furans, thieno[3,2-b]indoles, thieno[3,2-b]benzofurans, thieno[3,2-b]pyridine-5-ones, thieno[3,2-b]pyran-5-ones, thieno[3,2-b]isoquinolin-5-ones, thieno[3,2-b]chromen-5-ones, thieno[3,2-b]quinolin-9-ones, and thieno[3,2-b]chromen-9-ones have been developed via in situ or stepwise intramolecular heteroannulation of newly synthesized 4,5-substituted 3-amino- or 3-hydroxy 2-functionalized thiophenes. These substituted 3-amino/hydroxythiophenes were readily obtained in high yields from easily accessible precursors, in a sequential one-pot process, by treatment of a range of (het)aryl/unsubstituted acetonitriles or acetates with (het)aryl dithioesters in the presence of LDA, followed by in situ alkylation-intramolecular condensation of the resulting enethiolate salts with functionalized activated methylene halides. The functionalized activated methylene halides employed in these reactions for the synthesis of various thieno-fused heterocycles were cinnamyl bromide, 2-bromobenzyl chloride, bromocrotonate, 2-(bromomethyl)benzoate, and 2-chlorophenacyl bromide. A few of the 4,5-substituted 3-amino/hydroxy-2-stryrylthiophenes (or 2-acrylates) displayed strong fluorescence, and their absorption/emission spectra have also been examined.

ChemInform Abstract: (Thiolan‐2‐yl)diphenylmethyl Benzyl Ether/N,N′‐Diarylurea Cocatalyzed Asymmetric Aziridination of Cinnamyl Bromide and Aryl Aldimine

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ChemInform Abstract: Palladium‐Catalyzed Carbonylative α‐Arylation of tert‐Butyl Cyanoacetate with (Hetero)aryl Bromides.

AbstractA mild method is developed for the synthesis of a variety of β‐ketonitriles from aryl‐, hetaryl‐, and cinnamyl bromides, tert‐butyl 2‐cyanoacetate, and carbon monoxide using a two chamber system.

Copper‐Catalysed Allylic Substitution Using 2,8,14,20‐Tetrapentylresorcinarenyl‐Substituted Imidazolium Salts

AbstractUnsymmetrical imidazolium salts, each having one nitrogen atom (N1) substituted by a cavity‐shaped TPR group (TPR = 2,8,14,20‐tetrapentylresorcinaren‐5‐yl), were tested in situ as proligands for the copper‐catalysed allylic arylation of cinnamyl bromide with arylmagnesium halides. The catalytic systems produced mixtures of linear (l) and branched (b) arylated compounds in variable proportions, with the b/l ratio being the highest (78:22) for the most crowded imidazolium salt used, namely that in which the second nitrogen atom (N2) was substituted by a mesityl group. An N‐heterocyclic carbene complex obtained from one of the imidazolium salts was characterised by an X‐ray diffraction study.

ChemInform Abstract: Regio‐ and Enantioselective Copper‐Catalyzed Allylic Alkylation of ortho‐Substituted Cinnamyl Bromides with Grignard Reagents.

AbstractThe optimized procedure allows the access to the branched products with excellent regio‐ and enantioselectivity.

Regio- and enantioselective copper-catalyzed allylic alkylation of ortho-substituted cinnamyl bromides with Grignard reagents.

A highly efficient method for the copper-catalyzed asymmetric allylic alkylation of ortho-substituted cinnamyl bromides with Grignard reagents is reported. The use of a catalytic system comprising CuBr·SMe2 and TaniaPhos as chiral ligands gives rise to a range of branched products with excellent regio- and enantioselectivity.

(Thiolan-2-yl)diphenylmethyl benzyl ether/N,N′-diarylurea cocatalyzed asymmetric aziridination of cinnamyl bromide and aryl aldimine

A dual catalyst system using THT-based chiral sulfide 2a and H-bond donor 10a was developed for the asymmetric imino Corey–Chaykovsky reaction. Under the optimum reaction conditions, cinnamyl bromide reacted with a wide scope of N-diphenylphosphinic aldimines, to give the major trans-aryl cinnamyl aziridines with up to 98% ee. The role of H-bond donor 10a was demonstrated empirically as well.

ChemInform Abstract: Copper‐Catalyzed Domino Synthesis of Quinazolin‐4(3H)‐ones from (Hetero)arylmethyl Halides, Bromoacetate, and Cinnamyl Bromide.

Alkyl halides, including heteroarylmethyl and arylmethyl halides, bromoacetate, and cinnamyl bromide, are readily prepared via halogenation from basic raw materials, even using green processes. It is essential to replace their downstream products with them to prepare medicinally important heterocycles quinazolin-4(3H)-ones. Copper(I) bromide catalyzed domino reaction of alkyl halides and anthranilamides under air affords 2-substituted quinazolin-4(3H)-ones in good to excellent yields and with wide functional group tolerance. A mechanism for a copper(I) bromide involved organometal-catalyzed reaction via a four-step domino reaction is proposed.

Copper-Catalyzed Domino Synthesis of Quinazolin-4(3H)-ones from (Hetero)arylmethyl Halides, Bromoacetate, and Cinnamyl Bromide

Alkyl halides, including heteroarylmethyl and arylmethyl halides, bromoacetate, and cinnamyl bromide, are readily prepared via halogenation from basic raw materials, even using green processes. It is essential to replace their downstream products with them to prepare medicinally important heterocycles quinazolin-4(3H)-ones. Copper(I) bromide catalyzed domino reaction of alkyl halides and anthranilamides under air affords 2-substituted quinazolin-4(3H)-ones in good to excellent yields and with wide functional group tolerance. A mechanism for a copper(I) bromide involved organometal-catalyzed reaction via a four-step domino reaction is proposed.

ChemInform Abstract: Syntheses of Effectively‐Shielded N‐Heterocyclic Carbene Ligands.

AbstractNewly synthesized silver—carbene complexes are applied in the copper‐catalyzed allylic arylation of cinnamyl bromide with Grignard reagent (II) to form predominantly the gamma‐product (IV).

Synthesis of 3I-O and 2I-O-monosubstituted derivatives of per-6-azido-β-cyclodextrin—potential molecular scaffolds

Alkylation of per-6-azido-β-cyclodextrin by a suitable electrophilic reagent (cinnamyl bromide or propargyl bromide) gave a mixture of 3I-O and 2I-O regioisomers. After peracetylation and chromatographic separation on silica gel, pure isomers were isolated. Oxidative cleavage of cinnamyl double bond afforded the corresponding formylmethyl and carboxymethyl derivatives. The prepared scaffold molecules are equipped with two types of reactive groups which have a potential to serve as points of attachment for various compounds.

The design and synthesis of novel IBiox N-heterocyclic carbeneligands derived from substituted amino-indanols

A synthetic route towards a number of novel IBiox N-heterocyclic carbene (NHC) ligands has been developed. The resulting ligands have restricted flexibility and high steric demand. Preliminary studies have shown these ligands to give high levels of asymmetric induction in the copper-free allylic alkylation of cinnamyl bromide.