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The pathway for catalytic hydrodeoxygenation (HDO) of biomass-derived fast pyrolysis oil represents a compelling route for production of liquid transportation fuels. This is a review of the published research and patent literature in bio-oil HDO over the last 6 years performed with actual bio-oils and identifiable strategy for production of an infrastructure compatible liquid transportation fuel. Research is moving towards continuous, industrially relevant processes generating data to inform techno-economic analysis (TEA) and understand the nature of the fuels produced. Research gaps identified include: (1) focus on process integration; (2) developing appropriate quality metrics for intermediates; (3) evaluating research by TEA; and (4) meeting fuel functional requirements and comparison to ASTM standards for existing fuels.

A wide range of substituted and unsubstituted indoles and heterocyclic variants are obtained by microwave mediated Hemetsberger—Knittel cyclizations and tandem cyclization-decarboxylation.

[53210-13-2] C5H9CuSi (MW 160.78) InChI = 1S/C5H9Si.Cu/c1-5-6(2,3)4;/h2-4H3; InChIKey = DNXSGHQBAIKZLI-UHFFFAOYSA-N (coupling agent for introduction of the (trimethylsilyl)ethynyl group;2 preparation of mixed cuprates3) Alternate Names: copper(I) trimethylsilylacetylide. Physical Data: orange-red unstable solid. Solubility: sol THF, THF–HMPA mixtures; insol ether. Preparative Method: by treatment of Trimethylsilylacetylene with Copper(I) t-Butoxide,2 by addition of CuBrċSMe2 (see Copper(I) Bromide) to a THF solution of Lithium (Trimethylsilyl)acetylide,4 or by treatment of trimethylsilylacetylene with Triethyl Phosphite and Copper(I) Chloride.5 Handling, Storage, and Precautions: best generated in situ and used immediately.2 THF solutions are unstable above −20 °C.2 The solid is unstable, and all such copper(I) acetylides are potentially explosive. Use in a fume hood.

[55630-32-5] C6H11CuSi (MW 174.81) InChI = 1S/C6H11Si.Cu/c1-5-6-7(2,3)4;/h1H2,2-4H3; InChIKey = VKHYHOFWVNJNQN-UHFFFAOYSA-N (agent for the introduction of the trimethylsilylpropynyl group via 1,6-conjugate additions2 and vinyl substitutions;3 preparation of lithium bis(trimethylsilylpropynyl)cuprate4) Alternate Names: trimethylsilylpropargylcopper Physical Data: brown heterogenous solution in ether. Solubility: sol pyridine, THF; slightly sol ether. Analysis of Reagent Purity: addition of aqueous ammonium chloride gives >95% conversion to 1-trimethylsilylpropyne.2 Preparative Method: a solution of 1-Lithio-3-trimethylsilyl-1-propyne containing N,N,N′,N′-Tetramethylethylenediamine (TMEDA) in ether2 or THF is added to a slurry of Copper(I) Iodide in ether at −78 °C, then warmed to −10 °C and used immediately.3 Handling, Storage, and Precautions: dry copper(I) acetylides are potentially explosive. Use in a fume hood.

Coupling of the pyrazine (I) with arynes, generated in situ, followed by pyrazine ring cleavage allows access to various enantiomerically enriched α-arylglycines.

Positron emission tomography (PET) imaging of Alzheimer's Disease (AD) offers the potential to provide early onset diagnosis and subsequent intervention, including guided treatment regimens. One of the restricting factors in clinical application of PET technology is the limited availability of radioligands with affinity to specific targets of interest. Given the short half-life of the most popular positron emitter currently used ((18)F; approximately 120 min.) extremely rapid and efficient radiochemistry methods are needed to ensure required compounds are prepared and purified for administration within the 2-3 half life practical limit. Recent efforts to combine microwave mediated synthesis with advanced catalysis in the synthesis of specific categories of AD imaging agents will be presented.

The new carbinolamine-containing oxazolo[2,3-c][1,4]benzodiazepine ring system has been synthesized, and its reactivity and stability have been compared with properties of the analogous pyrrolo[2,1-c][1,4]benzodiazepine system found in the DNA-binding anthramycin antitumour antibiotics.

C 12 H 12 N 2 O 2 cristallise dans P2 1 avec a=8.717, b=6.927, c=10.950A, β=113.02°, Z=2; affinement jusqu'a R=0.040. C 17 H 18 N 2 O 7 cristallise dans P2 1 2 1 2 1 avec a=6.633, b=13.435, c=19.246A, Z=4; affinement jusqu'a R=0.040. Les deux molecules ont des conformations de type bateau similaires pour le cycle a sept chainons et le cycle a cinq chainons fusionne.

A one-pot tandem S N 2-Michael addition sequence has been developed for the preparation of five-membered- and six-membered-ring nitrogen and sulfur heterocycles from 6- or 7-halo-2-alkenoate esters. Nitrogen-containing rings are prepared by reaction of the ω-halo-2-alkenoate ester with a primary amine in the presence of triethylamine. The sulfur analogues are generated by thiourea displacement of the halide followed by base hydrolysis of the isotthiouronium salt. Yields are routinely in the 60-80% range. Experiments are described which elucidate the chronology of the reaction sequences

The reactions of phenylchlorocarbene (PCC) and diphenylcarbene (DPC) with carbon-chlorine bonds were investigated by laser flash photolysis techniques, product studies, and electrochemical methods. The data with both carbenes are consistent with a polar chlorine atom transfer to form radical pairs. The PCC reaction can be thought of as an inner sphere electron transfer from the carbene to the carbon-halogen bond in which there is partial carbon-halogen bond formation in the transition state. The transition state is thought to involve a crossing between closed- and open-shell singlet surfaces. The data obtained in the reaction of DPC with chlorine donors resembles the data obtained with PCC but is more difficult to interpret because the multiplicity of the state reacting with the C-Cl bond is unclear. 40 refs., 10 figs., 9 tabs.

The preparation of a rationally designed catalyst system derived from norephedrine is reported. The key stereodirective element emanates from a chromium tricarbonyl group complexed to one face of the aryl ring. The catalysts mediate the addition of diethyl zinc to a variety of aldehydes with extremely high enantioselectivity.

A chiral metallocyclic Lewis acid based catalyst system derived from norephedrine is reported. A key stereodirective element emanates from a tricarbonyl chromium (0) group complexed to the aryl ring. The catalysts mediate the addition of dialkyl zinc species to a variety of aldehydes with high enantioselectivity.

(Z)-1,6-[Bis (trimethylsilyl)]-hex-3-ene-1,5-diyne has been prepared in high yield and in one pot from trimethylsilylpropargyl bromide by a remarkably stereoselective tandem carbenoid coupling-HX elimination sequence.

A tandem dealkoxycarbonylation-Michael addition reaction has been developed as a synthetic route to highly functionalized carbocycles. Methyl esters, activated toward decarboxylation by an electron-withdrawing group at C-2 and tethered by a three- or four-carbon chain to an acrylate Michael acceptor, have been prepared and used as the cyclization substrates. Treatment of these compounds with LiCl in HMPA at 120 o C for 4 h results in selective S N 2 dealkylation of the methyl esters, decarboxylation, and cyclization of the intermediate anions by a Michael addition to the pendant acrylate moiety. This affords 45-90% of the cyclopentane- and cyclohexaneacetic esters substituted at C-2 by an electron-withdrawing group. Moderate to excellent selectivity (3:1-99:1) in favor of the product having the electron-withdrawing group trans to the acetic ester side chain is observed. The reaction works best for the preparation of five-membered rings, and cyclizations proceed most cleanly from substrates which cyclize through a tertiary carbanion. Synthetic and mechanistic details as well as optimization studies and product structure proofs are presented

The synthesis of the 7-methoxy-1,2-cyclopropapyrrolo[1,2-a]indoles (cyclopropamitosenes) 5 and the related indolequinone 6 is described.

Novel arene chromium carbonyl complexed mustard agents have been prepared. The metal carbonyl group modulates mustard alkylative ability as evidenced by 4-NBP assay. Antitumor evaluation against the human colon tumor line HCT-116 however showed no clear correlation between alkylative ability and antitumor activity of the mustard agents, in part a consequence of the inherent cytotoxicity of the metal carbonyl group in this screen.

Functionalised bioactive enediynes can be produced via an intramolecular carbenoid coupling of bis-prop-2-ynylic halides, and elaborated into useful synthons via their dicobalt hexacarbonyl complexes.

Enediyne estrogen conjugates have been prepared from readily available precursors. Enediyne 12 causes significant DNA strand scission at 10 −3 M, and has demonstrated cytotoxicity against the ER rich MCF-7 human breast cancer cell line.

An efficient route to oxo-enediynes is presented. A simple oxo-enediyne has been synthesized, which cyclizes to give an isochroman. The agent shows cytotoxicity for ER rich breast cancer cells and a model for its mode of action is proposed.

Regioselective substitution of the intercalative pyrrolo[9,10- b ]phenanthrene template was used to prepare an enediyne conjugate. The enediyne induced DNA strand scission at relevent concentration but proteolysis was not significant.