Tert Butyl propionate

A mild and efficient a-heteroarylation of simple esters and amides via nucleophilic aromatic substitution has been described <06OL1447>. Treatment of 2-chloro-benzo[//Jthiazole 99 with tert-butyl propionate in the presence of NaHMDS under nitrogen furnishes tert-butyl 2-(benzo[c(jthiazol-2-yl)propanoate 100. When the same reaction is preformed initially under nitrogen and then exposed to air, the hydroxylation product 101 is obtained. This method offers two desirable features that are either complementary or improvements to the palladium-catalyzed a-arylation reactions. First, heteroaryl chlorides... 

Enantioselective Aldol Reactions. The use of 1 for generating two contiguous stereocenters via an asymmetric aldol condensation has also been investigated,but only with marginal success. For example, reaction of the lithium enolate derived from tert-butyl propionate with the /Y-lithio derivative of 1, followed by condensation with benzaldehyde, provided a mixture of anti and syn aldol products in poor-to-modest % ee (eq 8). 

The impact of steric effects in the carboxylic ester has been examined with both isopropyl and tert-butyl propionate, and it appears that there is no significant difference in yields over that observed with ethyl propionate. 

For X-ray crystal structure of the E lithium enolate of tert-butyl propionate which provides structural evidence for the E ketene acetal see Seebach, D. Proceedings of the Robert A. Welch Foundation Conferences on Chemical Resarch, Houston, Texas, Nov. 7-9, 1984, pp. 93-145. 

Ta bl e 3.8 Thermooxidative resistance in polyamide 6 at various temperatures measured on 1 mm thick tensile bars AO I N, N -hexamethylene-bis-3-(3,5-di-tert-butyi4-hydroxy phenyl)-propionamide (irganox 1098), A02 3,6-oxy-i,8-octane-diyl-bis-(3-(4-hydroxy-3-methyl-5-tert-butyl)-propionate) (irganox 245) [86]... 

Tetrakis(methylene-3(3,5-di-tert-butyl-4-hydroxylphenyl)propionate)methane [6683-19-8]... 

Triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxy-phenyl)propionate] [36443-68-2]... 

Ammonium sulfate triolein, oleic acid, androsten-3,17-dione, xanthanonic acid, cholesterol-propionate, N-methy Ipheny lalanine, D-glucose fluorescence after heating to 150 — 180 °C, exposure to tert-butyl hypochlorite [203]... 

This modification was used in the synthesis of (-)-avenaciolide. The key step is the trans-diastereoselective Michael addition of the lithium enolate of tert-butyl 2-(phenylse-leno)propionate (THF, — 78 CC) to (R)-5-octyl-2(5//)-furanone and subsequent trans-diastereoselective iodonation318. u e... 

Successful results have been obtained (Renfrow and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, i o-butyl, sec.-butyl and iso-amyl acetates ethylenegl3rcol diacetate ethyl monochloro- and trichloro-scetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyi adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, tert.-butyl acetate, n-octadecyl propionate, ethyl and n-butyl stearate, phenyl, benzyl- and g aicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

Esters 4-5.3 ppm Bis(2-ethylhexyl) adipate Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate... 

Pentaerythrltyl tetrakis (3,5-dl-tert-butyl-4-hydroxyphenyl)propionate (0.05) 35... 

PM 94400 36443-68-2 Irganox 245 Triethyleneglycol bis[3-(3-tert-butyl-4-hydroxy-5methylphenyl) propionate] 586.37 4 585.3 367.2, 409.2... 

METHYL ISOBUTYL KETONE n-PENTYL FORMATE n-BUTYL ACETATE sec-BUTYL ACETATE tert-BUTYL ACETATE ETHYL n-BUTYRATE ETHYL ISOBUTYRATE ISOBUTYL ACETATE n-PROPYL PROPIONATE CYCLOHEXYL PEROXIDE DIACETONE ALCOHOL 2-ETHYL BUTYRIC ACID n-HEXANOIC ACID 2-ETHOXYETHYL ACETATE HYDROXYCAPROIC ACID PARALDEHYDE... 

Opening of the dithiazole ring of the imidazolo[4,5-r7 [l,2,3]dithiazole 107 was employed as a key step in a multistep synthesis leading to hydroxamic acid derivatives 108 and 109 which are under investigation as matrix metalloproteinase inhibitors. Following initial reaction of 107 with NaOH treatment with 2-bromo-3-(4-chlorophenyl)propionic acid tert-butyl ester lead to the thioethers 108 from which 109 could be obtained (Scheme 10). <2000W0063197>. 

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