Propionic 3-bromo

Propionic acid, 2-bromo-3-(3-indolyl)-methyl ester rearrangement, 4, 279 Propionic acid, 3-(3,4-dimethyoxyphenyl)-dihydrocoumarin synthesis from, 3, 848 Propionic acid, indolyl-synthesis, 4, 232 Propionic acid, 3-(l-indolyl)-sodium salt pyrolysis, 4, 202 Propionic acid, 3-(3-indolyl)-intramolecular acylation, 4, 220, 221 Propionic acid, 3-phenoxy-chroman-4-one synthesis from, 3, 855 Propionic acid, 3-(3-phenylisoxazoI-5-yl)-bromination, 6, 25... 

Chloro-2,2,3-trifluoropropionic acid has been prepared by permanganate oxidation of 3-chloro-2,2,3-trifluoropropanol which is one of the telomerization products of chlorotrifluoroethylene with methanol. The present procedure is a modification of one reported earlier and is undoubtedly the method of choice for making propionic acids containing 2 fluorine atoms, i.e., 2,2,3,3-tetrafluoropropionic acid, 3,3-dichloro-2,2-difluoropropionic acid, and 3-bromo-2,2,3-trifluoropropionic acid. When preparing 2,2,3,3-tetrafluoropropionic acid from tetrafluoroethylene, it is desirable to use an additional 50 ml. of acetonitrile and externally applied heat to initiate the reaction. 

The member of this class which has been studied most thoroughly is 2-benzylidene-4-methyl-5(2 )-oxazolone (57). This compound may be prepared by ring closure of either 3-bromo-2-phenylacetamido-propionic acid or A-(a-halophenylacetyl)alanine (56) [Eq. (30)]. These reactions presumably proceed via unstable halogeno-5(4IT)-oxazolones, which rapidly lose hydrogen halide. 

The compound 2-amino-2, 6 -propionoxylidide was synthesized by saturating with gaseous ammonia at room temperature a suspension of 50 g (0.195 mol) of 2-bromo-2, 6 -propion-oxylidide in a mixture of 500 ml of 95% alcohol and 400 ml of concentrated aqueous ammonia. The saturation was carried out under mechanical stirring. After 25 hours the mixture was resaturated with ammonia gas. The stirring at room temperature was continued for a total period of 116 hours, and a sample was taken at that time. Gas chromatographic analysis indicated that about 95% of the bromo compound had been converted to the desired product. 

Ethyl a-bromobutyrate Cyclobutyrol Ethyl bromoisobutyrate Methallenestril Ethyl-2-bromo propionate Naproxen Ethyl carbonate Ibuprofen Ethyl chloride Oxeladin... 

Johnson s classic synthesis of progesterone (1) commences with the reaction of 2-methacrolein (22) with the Grignard reagent derived from l-bromo-3-pentyne to give ally lie alcohol 20 (see Scheme 3a). It is inconsequential that 20 is produced in racemic form because treatment of 20 with triethyl orthoacetate and a catalytic amount of propionic acid at 138 °C furnishes 18 in an overall yield of 55 % through a process that sacrifices the stereogenic center created in the carbonyl addition reaction. In the presence of propionic acid, allylic alcohol 20 and triethyl orthoacetate combine to give... 

Propionic acid, 2-iodo-3-nitro-, ethyl ester [Propanoic acid, 2-iodo-3-mtro-, ethyl ester], 65 2//-Pyran, 3,4-dihydro-, 51 2//-PYR AN-2-ONE, 49 2H Pyran 2-one, 5 bromo 5,6-dihydro, 50 27/-PYRAN-2-ONE, 5,6 DIHYDRO-, 49 PYRIDINE, 2,3,4,5 TETRAHYDRO, 118 Pyridines, -substituted, 34 a Pyrone-6-carboxyhc acid [2H Pyran-6-Larboxyhc acid 2-oxo ], 51 Pyrroles, 34... 

Tocopheryl)propionic acid (50) is one of the rare examples that the o-QM 3 is involved in a direct synthesis rather than as a nonintentionally used intermediate or byproduct. ZnCl2-catalyzed, inverse hetero-Diels-Alder reaction between ortho-qui-none methide 3 and an excess of <2-methyl-C,<9-bis-(trimethylsilyl)ketene acetal provided the acid in fair yields (Fig. 6.37).67 The o-QM 3 was prepared in situ by thermal degradation of 5a-bromo-a-tocopherol (46). The primary cyclization product, an ortho-ester derivative, was not isolated, but immediately hydrolyzed to methyl 3-(5-tocopheryl)-2-trimethylsilyl-propionate, subsequently desilylated, and finally hydrolyzed into 50. 

The reaction of potassium 3-amino-4-oxo-3,4-dihydroquinazoline-2-thiolate 62 with a-bromophenylacetic acid 63 resulted in the formation of (3-amino-4-oxo-3,4-dihydroquinazolin-2-ylsulfanyl)-phenyl-acetic acid methyl ester 64 which on alkali treatment and subsequent acidification resulted in the synthesis of 2-phenyl- 1-thia-4,4a,9-triaza-anthracene-3,10-dione 65 <1999JCR(S)86>. Similarly, the reaction of potassium 3-amino-5,6-dimethyl-4-oxo-3,4,4a,7a-tetrahydrothieno[2,3- pyrimidine-2-thiolate 66 with a-bromo-ester 67 resulted in the formation of 2-(3-amino-5,6-dimethyl-4-oxo-3,4,4a,7a-tetrahydrothieno[2,3- / pyrimidin-2-ylsulfanyl)-propionic acid ethyl ester 68. Subsequent treatment with alkali followed by acidification resulted in the formation of 2,3,7-trimethyl-3a,9a-dihydro-l,8-dithia-4a,5,9-triazacyclopenta[ ]naphthalene-4,6-dione 69 <2000JHC1161>... 

Monofunctional 2-bromo-2-methylpropionic acid 4-methoxyphenyl ester and difunctional l,4-(2/-bromo-2/-methyl-propionate)benzene initiators, given in Scheme 26, were employed for the polymerization of n-BuMA followed by the addition of DMAEMA, thus leading to the formation of PnBuMA-fo-PDMAEMA block and PDMAEMA-b-PnBuMA-h-PDMAEMA tri-... 

ABA triblock copolymers, where A was PBd and B either PS or PMMA were prepared by the combination of ROMP and ATRP techniques [122], The PBd middle blocks were obtained through the ROMP of cyclooctadi-ene in the presence of l,4-chloro-2-butene or cis-2-butene-l,4-diol bis(2-bromo)propionate using a Ru complex as the catalyst. The end allyl chloride or 2-bromopropionyl ester groups were subsequently used for the ATRP of either styrene or MMA using CuX/bpy (X = Cl or Br) as the catalytic system (Scheme 50). Quantitative yields but rather broad molecular weight distributions (Mw/Mn higher than 1.4) were obtained. 

Miktoarm stars of the A(BC)2 type, where A is PS, B is poly(f-bulyl acrylate) (PtBA), and C is PMMA [161] have been synthesized, by using the trifunctional initiator 2-phenyl-2-[(2,2,6,6-tetramethyl)-l-piperidinyloxy] ethyl 2,2-bis[methyl(2-bromopropionato)] propionate (NMP, ATRP) (Scheme 86). In the first step, a PS macroinitiator with dual < -bromo functionality was obtained by NMP of styrene in bulk at 125 °C. This precursor was subsequently used as the macroinitiator for the ATRP of ferf-bulyl acry-... 

This ester has been prepared by the action of ethyl jS-bromo-propionate on methylamine hydrochloride in the presence of silver oxide,1 by the addition of methylamine to ethyl acrylate,2 and by heating ethyl /3-chloropropionate, methylamine, and benzene in an autoclave.3... 

In a more detailed study, the same esterase P. fluorescens) was again subjected to mutagenesis using the same mutator strain, but also by saturation mutagenesis at selected positions 133a). In addition to 3-phenylbutyric acid ethyl ester (27), 3-bromo-2-methyl-propionic acid methyl ester rac-31) was chosen for the hydrolytic kinetic resolution, with the WT PFE showing an E factor of 12 in favor of the (5)-32. 

Automated parallel experiments were carried out to rapidly screen and optimize the reaction conditions for ATRP of methyl methacrylate (MMA) [34]. A set of 108 different reactions was designed for this purpose. Different initiators and different metal salts have been used, namely ethyl-2-bromo-tTo-butyrate (EBIB), methyl bromo propionate (MBP), (1-bromo ethyl) benzene (BEB), and p-toluene sulfonyl chloride (TsCl), and CuBr, CuCl, CuSCN, FeBr2, and FeCl2, respectively. 2,2 -Bipyridine and its derivatives were used as ligands. The overall reaction scheme and the structure of the used reagents are shown in Scheme 2. 

Estradiol methylether acetate, or 4-Bromo or 4-Chloroestradiol diacetate 3-( 1 P-Acetoxy-8p-methyl-5p-carboxy-trani-perhydroindanyl-4a) propionic acid C [250]... 

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>. 

---