Elliotts Alcohol

Industrial preparation of resmethrin, one of the first members of the pyrethroid family to be introduced, is achieved via Elliott s alcohol. Available procedures make use of stoichiometric amounts of pyridine, thionyl chloride and fuming nitric acid, and a lot of chlorinated by-products are generated. We present here an alternative route to Elliott s alcohol, based on the Baylis-Hillman reaction in aqueous media. A comparative quantitative assessment of the greenness has been performed, using the freeware package EATOS, which takes into account both the mass economy and the environmental impact of the materials involved. 

Bioresmethrin is one of the most effective broad spectrum insecticides currently available. It exhibits a high order of insecticidal activity, which is coupled with its excellent toxicological properties [14]. 

They are both chrysanthemic acid esters of (5-benzylfuran-3-yl)methanol (Elliott alcohol, 1) [15]. Patented methods [16] for the industrial preparation of Elliotf s alcohol are demanding or such as to be hardly exploited in industrial-scale plants. For instance, in one of these methods [17] (5-benzyl-3-furyl)methanol is obtained by a sequence of Claisen condensation of benzyl cyanide and a dialkyl succinate, hydrolysis, esterification, protection of the ketone group, formylation, cyclization to 5-benzyl-3-furfuryl ester and reduction to alcohol with lithium aluminium hydride. 

The process is particularly laborious, it requires anhydrous solvents and uses lithium aluminium hydride, the handling of which requires numerous precautions. 

Of course, this preparation poses a heavy burden on the environment. In the first step, huge amounts of pyridinium salts and SO2 are generated along with 20% of a tetrachlorinated by-product that has no use but which has to be discarded in the following step. The second step is accompanied by a large NOx evolution, while the final step releases carbon dioxide and HCl. 

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Pyrethrolone and cinerolone make up the keto alcohol moiety of the pyrethrins. Both of these keto alcohols have one asymmetric carbon at the 4-position and a double bond in the side chain which is capable of cis-trans isomerism in the 2-position. It is possible, therefore, to have four stereoisomers for each keto alcohol. Katsuda et al. (22) show that only the ( + ) form occurs in the natural esters. Elliott (8) has shown recently, by a new procedure developed to obtain pure ( + ) pyrethrolone, that the hitherto unidentified prye-throlone C is in reality pyrethrolone contaminated with thermally isomerized material. (+) Pyrethrolone forms a crystalline monohydrate from which the pure alcohol is obtained. The natural configurations of the keto alcohols in the esters are insecticidally more active, as is the case with the acid moiety. 

Elliott YS (2000). Lab test offers new way to spot alcoholism. Viewed at http //www.ama-assn.org/sci-pubs/amnews/pick 00/hlsc0828.htm... 

The most important breakthrough in terms of modifications of the alcohol moiety of pyrethrins was the aforementioned piperonyl ester (3) followed by the inventions of resmethrin (7) by Elliott in 1965 [5] and phenothrin (5) by Itaya in 1968 [6]. Further exploratory work in Sumitomo Chemical on modification of... 

Procedures for the isolation and characterization of trace gases and odorants in the dust from pig houses are given by SCHAEFER et al. (29), HAMMOND et al.(30) and TRAVIS and ELLIOTT (31). Alcoholic solvents were found to be effective for the extraction of volatile fatty acids and phenols from the dust of hen (32) and pig houses (33), (34). Today, gas chromatography is usually used for the separation and identification of the trace gases. Table IV gives a literature review of compounds identified in the dust of pig houses. There are only very few reports on investigations on the dust from hen houses (32). 

Bartlett PA, Johnson WS, Elliott JD (1983) Asymmetric synthesis via acetal templates. 3. On the stereochemistry observed in the cyclization of chiral acetals of polyolefinic aldehydes formation of optically active homoallylic alcohols. J Am Chem Soc 105 2088-2089... 

An example of 2,4,6-triphenylpyrylium-3-olate (65 R = R = R = Ph, R = H) reacting as a 1,3-dipole was first provided by Suld and Price who obtained a maleic anhydride adduct (C25HigO5). Subsequently, an extensive study of the cycloadditions of this species has been published by Potts, Elliott, and Sorm. With acetylenic dipolarophiles, compound 65 (R = R = R = Ph, R = H) gives 1 1 adducts that have the general structure 74 and that isomerize to 6-benzoyl-2,4-cyclohexadienones (76) upon thermolysis. This thermal rearrangement (74 -> 76) has been interpreted in terms of an intermediate ketene 75. The 2,3-double bond of adduct 74 (R = Ph) is reduced by catalytic hydrogenation. Potential synthetic value of these cycloadducts (74) is demonstrated by the conversion of compound 74 (R = Ph) to l,2,3,4,6-pentaphenylcyclohepta-I,3,5-triene (79 R= Ph) via the alcohol 78 (Scheme 1). ... 

Infra-red dichroism has been used in studies of polymer specimens in which the chain molecules are parallel to each other, to give evidence on the orientation of particular atomic groups. In nylon and polyvinyl alcohol (Ambrose, Elliott, and Temple, 1949), Terylene (Miller and Willis, 1953), and polytetrafluoroethylene (Liang and Krimm, 1956) the results are consistent with structures already established by X-ray methods. Turning to more complex structures not yet solved in detail by X-ray methods, infra-red dichroism has indicated that in cellulose... 

The spectrum of polyvinyl alcohol (PVA), -(CH2CHOH)n, was the subject of much early study [Thompson and Tor-kington (228)] Elliott, Ambrose, and Temple (53) Blout and Karplus (77) Ambrose, Elliott, and Temple (6) Glatt, Webber, Seaman, and Ellis (66) Glatt and Ellis (65)], but with only... 

Firoozi S, Elliott PM, Sharma S, et al. Septal myotomy-myectomy and transcoronary septal alcohol ablation in hypertrophic obstructive cardiomyopathy. A comparison of clinical, haemodynamic and exercise outcomes. Eur Heart J 2002 23 1617-1624. 

Preparation. Potts and Elliott have reported an improved procedure for conversion of o-dibenzoylbenzene (1) into diphenylisobenzofurane (4). Reduction of (1) with excess sodium borohydride, followed by treatment with hot acetic anhydride, provides (4) in yields around 70%. Isolation of the intermediate alcohol (2) is not necessary. 

Spectra of Crystals Infrared Dichroism. The spectrum of a single crystal observed in polarized light depends upon the orientation of the crystal axes relative to the plane of polarization. A similar situation exists for macroscopically oriented high polymers, obtained by extruding or stretching polymeric materials such as nylon, polyvinyl alcohol, and polyethylene. Ellis and co-workers were the first to make systematic studies of IR dichroism in H bonded systems (604, 779, 780). Further attention was drawn to the method by Mann and Thompson (1334), Crooks (463), and Ambrose, Elliott, and Temple (595, 38, 589, 4). 

By proceeding stepwise with a series of suitable indicators (Minnick and Kilpatrick, 68) the whole scale of relative acidity for any one solvent can be covered. Kilpatrick and Hears (69) have determined the relative acid strengths of the monosubstituted benzoic acids in the solvents methyl and ethyl alcohol and compared the results with the direct determinations of the equilibrium constants (Elliott and Kilpatrick, 70) for reactions as expressed in equation (23). Difficult extrapolations in equation (22) can be avoided if the indicator and other acid are of the same charge type. Measurements of this type yield relative acid strengths in a particular solvent without any nonthermodynamic assumptions. 

Unlu, O. Gray, N. Gerek, Z.N. Elliott, J.R. Transferable step potentials for the straight chain alkanes, alkenes, alkynes, ethers, and alcohols. Ind. Eng. Chem. Res. 2004, 43, 1788-1793. 

Introducing Green Metrics Early in Process Development. Comparative Assessment of Alternative Industrial Routes to Elliott s Alcohol, A Key Intermediate in the Production of Resmethrins... 

Scheme 16.1 Previous procedure for the preparation of Elliott s alcohol (1).

Comparative Assessment of the Two Alternative Routes to Elliott s Alcohol 555... 

Consequently, a comparative quantitative assessment of the two routes was needed. This quantitative greenness assessment compares the two alternative routes the best existing one (Schemes 16.1 to 16.3) [18] and the new route (Scheme 16.4). Both routes are compared up to the common Elliott s alcohol intermediate 4. Scheme 16.5 depicts the two different routes. 

Scheme 16.5 Alternative routes to the common intermediate 4 to Elliott s alcohol.

Figure 16.4 reveals that route B also allows a decrease (33%) in the potential environmental impact of materials used for the preparation of Elliott s alcohol intermediate 4. Again, most the hazards and costs come from the use of auxiliaries. For route A a significantly higher proportion of the potential environmental impact of the materials used is due to reaction substrates (green block) and especially to thionyl chloride. 

This chapter has presented a quantitative assessment of the environmental impact of two alternative procedures for the preparation of Elliott s alcohol. The assessment was made with the aid of the EATOS tool. This is an easy to use software tool that can be used routinely to assess the greenness of reactions or synthetic schemes. Its simplicity allows for a daily routine use, thus favoring the introduction of green elements at a very early stage of synthetic process design. 

The only other noticeable effect of variation of the experimental parameters shown (Table I) is a negative effect of high alkali concentration on oil yield, when the sodium carbonate concentration is raised to 2.37 N (12.6%) at 270-343 C. This is counter to Elliott and Giacoletto s results (10). The effect of alkali on cellulose chain peeling and cleavage was found to be directly proportional to alkali concentration at lower temperatures (185 C) (47). Since high alkali concentrations favor the hydride- transfer mediated Cannizzaro reaction to yield acid salts and alcohols from aldehydes and some ketones, we suggest that perhaps the lower oil yield may be due to removal of carbonyl intermediates from the reaction. 

From 1967, the efforts of Michael EUiott at Rothamsted (England) produced pyrethroids of ever increasing potency, suited for bulk production, and useful in agriculture. The first of these, bioresmethrin (Elliott et aL, 1967), in which chrysanthemic acid is esterified with a furan-derived alcohol 6.53), proved to be the first synthetic substance with the full potency of pyrethrum I against a wide range of insects. It is non-toxic to mammals, and is still much used in market gardens, particularly on carrots, cabbage, and lettuce. 

The modern cubic equations of state provide reliable predictions for pure-component thermodynamic properties at conditions where the substance is a gas, liquid or supercritical. Walas and Valderrama provided a thorough evaluation and recommendations on the use of cubic equation of state for primary and derivative properties. Vapour pressures for non-polar and slightly polar fluids can be calculated precisely from any of the modem cubic equations of state presented above (Soave-Redlich-Kwong, Peng-Robinson or Patel-Teja). The use of a complex funetion for a (such as those proposed by Twu and co-workers ) results in a significant improvement in uncertainty of the predicted values. For associating fluids (such as water and alcohols), a higher-order equation of state with explicit account for association, such as either the Elliott-Suresh-Donohue or CPA equations of state, are preferred. For saturated liquid volumes, a three-parameter cubic equation of state (such as Patel-Teja) should be used, whereas for saturated vapour volumes any modern cubic equation of state can be used. 

Hu, J., Wang, Y., Cao, C, Elliott, D.C., Stevens, D.J., and White, J.F. (2007) Conversion of biomass-derived syngas to alcohols and C2 oxygenates using supported Rh catalysts in a microchannel reactor. Catal Today,... 

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