Peterson 2-selective

S.G. Vitols, M. Masquelier and C.O. Peterson, Selective uptake of a toxic lipophilic anthracycline derivative by the low-density lipoprotein receptor pathway in cultured fibroblasts, J. Med. Chem. 28 (1985) 451-454. 

The following acid-catalyzed cyclizations leading to steroid hormone precursors exemplify some important facts an acetylenic bond is less nucleophilic than an olelinic bond acetylenic bonds tend to form cyclopentane rather than cyclohexane derivatives, if there is a choice in proton-catalyzed olefin cyclizations the thermodynamically most stable Irons connection of cyclohexane rings is obtained selectively electroneutral nucleophilic agents such as ethylene carbonate can be used to terminate the cationic cyclization process forming stable enol derivatives which can be hydrolyzed to carbonyl compounds without this nucleophile and with trifluoroacetic acid the corresponding enol ester may be obtained (M.B. Gravestock, 1978, A,B P.E. Peterson, 1969). 

For the purpose of stereoselective synthesis the selective elimination at the stage of the /3-hydroxysilane 5 is not a problem the diastereoselective preparation of the desired /3-hydroxysilane however is generally not possible. This drawback can be circumvented by application of alternative reactions to prepare the /3-hydroxysilane 2 however these methods do not fall into the category of the Peterson reaction. 

The surprising selectivity in the formation of 4 and 5 is apparently due to thermodynamic control (rapid equilibration via the 1,3-boratropic shift). Structures 4 and 5 are also the most reactive of those that are present at equilibrium, and consequently reactions with aldehydes are very selective. The homoallylic alcohol products are useful intermediates in stereoselective syntheses of trisubstituted butadienes via acid- or base-catalyzed Peterson eliminations. 

Hugget D, Brook B, Peterson B, Foran CM, Schlenk D (2002) Toxicity of selected beta adrenergic receptor-blocking pharmaceuticals (B-blockers) on aquatic organisms. Arch Environ Contam Toxicol 43 229-235... 

Hnggett, D.B., Brooks, B.W., and Peterson, B. et al. (2002). Toxicity of select beta adrenergic receptor blocking pharmaceuticals (beta blockers) on aqnatic organisms. Archives Environmental Contamination and Toxicology 41, 229-235. 

Although several data sets could be used to derive AEGL-3 values, the 1-h exposure data from the mouse study by Peterson and Bhattacharyya (1985) provided the most sound basis and were selected to derive AEGL-3 values. Due to the steep concentration-response curve for arsine, the 15-ppm exposure (where there was no lethality) was considered an estimate of the lethality threshold. An uncertainty factor of 30-fold was applied to account for interspecies extrapolation (10-fold) and intraspecies variability (3-fold) (see Section 6.3). 

Peterson methylenation (10, 433 11, 581). Methylenation with trimethyl-silylmethyllithium, (CH3),SiCH2Li, is not widely used in synthesis because of lack of selectivity and moderate yields. However, a modified reagent prepared from (CH3)3SiCH2Li and CeCl, adds to aldehydes or ketones (even enolizable ones) to form adducts in generally high yield, particularly in the presence of TMEDA. The 2-hydroxysilanes are converted into methylene compounds by aqueous HF (with or without pyridine).4... 

Hedges, J.I., J.A. Baldock, Y. Gelinas, C. Lee, M.L. Peterson, and S.G. Wakeham. 2001. Evidence for non-selective preservation of organic matter in sinking marine particles. Nature 409 801-804. 

D. C. Peterson, The Medicinal Chemistry of the Selected Glycine-Containing Cyclic Dipeptides Cyclo(Gly-L-Val) and Cyclo(Gly-L-Val). Dissertation, Magister Scientiae, Faculty of Health Sciences, Nelson Mandela Metropolitan University, 2006. 

Peterson olefination, a silicon variant of the Wittig reaction, has been used to convert a-silyl benzyl carbamates (78) into trisubstituted vinyl carbamates (79) in moderate-to-good yields and with some ii/Z-selectivity. ... 

The effects of solvent, temperature, and bulk of the silyl and carbamate functionalities on the stereochemistry of Peterson oleflnations of silylated benzyl carbamates (to give substituted vinyl carbamates) has been investigated. Steric/electronic bulk of the triphenylsilyl moiety appears to be the overriding factor in promoting Z-selectivity. 

Peterson and Scarrah 165) reported the transesterification of rapeseed oil by methanol in the presence of alkaline earth metal oxides and alkali metal carbonates at 333-336 K. They found that although MgO was not active for the transesterification reaction, CaO showed activity, which was enhanced by the addition of MgO. In contrast, Leclercq et al. 166) showed that the methanolysis of rapeseed oil could be carried out with MgO, although its activity depends strongly on the pretreatment temperature of this oxide. Thus, with MgO pre-treated at 823 K and a methanol to oil molar ratio of 75 at methanol reflux, a conversion of 37% with 97% selectivity to methyl esters was achieved after 1 h in a batch reactor. The authors 166) showed that the order of activity was Ba(OH)2 > MgO > NaCsX zeolite >MgAl mixed oxide. With the most active catalyst (Ba(OH)2), 81% oil conversion, with 97% selectivity to methyl esters after 1 h in a batch reactor was achieved. Gryglewicz 167) also showed that the transesterification of rapeseed oil with methanol could be catalyzed effectively by basic alkaline earth metal compounds such as calcium oxide, calcium methoxide, and barium hydroxide. Barium hydroxide was the most active catalyst, giving conversions of 75% after 30 min in a batch reactor. Calcium methoxide showed an intermediate activity, and CaO was the least active catalyst nevertheless, 95% conversion could be achieved after 2.5 h in a batch reactor. MgO and Ca(OH)2 showed no catalytic activity for rapeseed oil methanolysis. However, the transesterification reaction rate could be enhanced by the use of ultrasound as well as by introduction of an appropriate co-solvent such as THF to increase methanol solubility in the phase containing the rapeseed oil. 

A. Najafi, A. Peterson, M. Buchsbaum, S. O Dell, F. Weihmuller, Preparation and preliminary biological evaluation of [F-18]NCQ-115—A new selective reversible dopamine D2 receptor ligand, Nucl. Med. Biol. 20 (1993) 549-555. 

Bernard ML, Peterson YK, Chung P, Jourdan J, Lanier SM (2001) Selective interachon of AGS3 with G-proteins and the influence of AGS3 on the achvahon state of G-proteins. J Biol Chem 276 1585—1593... 

Wadge, A., Hutton, M. Peterson, P. J. 1986. The concentration and particle size relationships of selected trace elements in fly ashes from U.K coal-fired power plants and a refuse incinerator. Science of the Total Environment, 54, 13-27. 

After rotation about the newly formed bond, nothing stands in the way of selective -elimination from 47 - a possible intermediate of a base-induced Peterson elimination - to Z-olefin 48.18... 

Arndtsen, B.A., Bergman, R.G., Mobley, T.A. and Peterson, T.A. (1995) Selective intermolecular carbon—hydrogen bond activation by synthetic metal complexes in homogeneous solution. Acc. Chem. Res., 28, 154. 

Addition of dimethylsulfonium methylide (122) to various Michael acceptors (121), followed by alkylation, has been reported to produce functionalized 1-substituted alkenes (124), arising via the unprecedented elimination (123), rather than the usual cyclopropanation products. In silyl substituted substrates, where a facile Peterson-type olefination is possible from the adduct, elimination took place instead. Aryl-substituted Michael acceptors (121 R1 = Ar) underwent a similar olefination to give 1-substituted styrene derivatives with moderate yields along with a side product, which arose by nucleophilic demethylation from the adduct of dimethylsulfonium methylide and arylidene malonates. Hammett studies revealed that selectivity for olefination versus demethylation increases as the aryl substituent becomes more electron deficient.164... 

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