Lactones propiolactone

Along with other lactones, propiolactone has been studied to test its isotropic action of the isolated hypodynamic papillary musde of the cat, wilhout positive results. ... 

Further support is obtained from experiments carried out by other workers with the parent lactone, / -propiolactone. For instance, NMR and chemical evidence have been presented for the initiation reactions with triethylphosphine (I) and trimethylamine (2). Studies (3) have... 

P-Lactones (propiolactones) too are readily attacked at the carbonyl carbon, for example they are particularly easily hydrolysed, but a second mode of nucleophilic attack - Sn2 displacement of carboxylate via attack at C-4 - occurs with many nucleophiles. The example shows the use of a homochiral P-lactone, available from serine. 

The carbonylation of COD PdCl2 complex in aqueous sodium acetate produces /rui7x-2-hydroxy-5-cyclooctenecarboxylic acid /i-lactone (240). The lactone is obtained in 79% yield directly by the carbonylation of the COD complex in aqueous sodium acetate solution[220]. /i-Propiolactone (241) is obtained in 72% yield by the reaction of the PdCC complex of ethylene with CO and water in MeCN at —20 " C. /3-Propiolactone synthesis can be carried out with a catalytic amount of PdCC and a stoichiometric amount of CuCl2[221]. 

Indoles can also be alkylated by lactones[l4]. Base-catalysed reactions have been reported for (3-propiolactone[15], y-butyrolactone[10] and 5-valerolac-tone[10]. These reactions probably reflect the thermodynamic instability of the N -acylindole intermediate which would be formed by attack at the carbonyl group relative to reclosure to the lactone. The reversibility of the JV-acylation would permit the thermodynamically favourable N-alkylation to occur. 

P-Hydroxy acids lose water, especially in the presence of an acid catalyst, to give a,P-unsaturated acids, and frequendy P,y-unsaturated acids. P-Hydroxy acids do not form lactones readily because of the difficulty of four-membered ring formation. The simplest P-lactone, P-propiolactone, can be made from ketene and formaldehyde in the presence of methyl borate but not from P-hydroxypropionic acid. P-Propiolactone [57-57-8] is a usehil intermediate for organic synthesis but caution should be exercised when handling this lactone because it is a known carcinogen. 

Reaction with Lactones. Hydroxycarboxyhc acid ester complexes of titanium are formed by reaction of a tetraalkyl titanate with a lactone, such as P-propiolactone, y-butyrolactone, or valerolactone (35). For example. 

An alternative route to acrylic esters is via a (3-propiolactone intermediate. The lactone is obtained by the reaction of formaldehyde and ketene, a dehydration product of acetic acid ... 

A 1992 patent describes the carbonylation of EO to yield /3-propiolactone using a mixture of Co2(CO)8 and 3-hydroxypyridine.982 A recent re-investigation of this system has indicated that the major product is the alternating copolymer, a polyester, catalyzed by the [Co(CO)4] anion (Scheme 24).983 The synthesis of lactones via this methodology has successfully been achieved using Lewis acidic counter-cations (Scheme 25) 984,985 a similar strategy allows /3-lactams to be... 

Synonyms AI3-24257 AIDS-6024 Betaprone BPL BRN 0001360 Caswell No. 709 CCRIS 536 EINECS 200-340-1 EPA pesticide chemical code 010901 Hydracrylic acid p iactone 3-Hydroxypropionic acid lactone p Lactone NSC 21626 Oxetan-2-one 2-Oxetanone Propano-lide Propiolactone 1,3-Propiolactone 3-Propiolactone p Propionolactone 3-Propionolactone p Propro-lactone UN 2810. 

Hydracrylic acid p-lactone, see p-Propiolactone Hydralin, see Cyclohexanol Hydrazine-benzene, see Phenylhydrazine Hydrazinobenzene, see Phenylhydrazine Hydrazobenzene, see 1,2-Diphenylhydrazine l,T-Hydrazobenzene, see 1,2-Diphenylhydrazine Hydrazodibenzene, see 1.2-Diphenylhydrazine Hydrazomethane, see Methylhydrazine Hydrindane, see Indan... 

Hydroxyphenol, see Hydroquinone p-Hydroxyphenol, see Hydroquinone 4-Hydroxy-3-(l-phenyl-3-oxobutyl)coumarin, see Warfarin 1 -Hydroxypropane, see 1 -Propanol 3 Hydroxypropene, see Allyl alcohol 3 Hydroxypropionic acid lactone, see p-Propiolactone... 

Epoxides readily undergo anionic copolymerization with lactones and cyclic anhydrides because the propagating centers are similar—alkoxide and carboxylate [Aida et al., 1985 Cherdron and Ohse, 1966 Inoue and Aida, 1989 Luston and Vass, 1984]. Most of the polymerizations show alternating behavior, with the formation of polyester, but the mechanism for alternation is unclear. There are few reports of cationic copolymerizations of lactones and cyclic ethers other than the copolymerizations of [5-propiolactone with tetrahydrofuran and... 

Lactones are easily polymerized by both cationic and anionic initiators, and in fact they (particularly /3-propiolactone) are known to polymerize explosively and unpredictably without addition of any initiators. Inhibitors, such as trialkylborates, have been used to prevent undesired polymerization (73GEP2255194). 

Reaction with ammonia and primary and secondary amines can also give two types of products, 0-hydroxyamides or amino acids (equation 49). The amide is obtained from the reaction of 0-propiolactone with ammonia in water, while the amino acid is obtained from the reaction in acetonitrile, both in good yield. 0-Lactones react very generally with both aliphatic and aromatic amines, but the type of product does not correlate with polarity of solvent or basicity of amine. Fortunately, conditions can usually be found for the formation of the desired product. 

The reaction of several a-amino acid esters with 0-lactones in chloroform solution gave hydroxyamide esters (equation 50), said to be useful fungicides (74JAP(K)74127918>. Enamines derived from cyclohexanone react smoothly with 0-propiolactone to give 3-(2-cyclo-hexanonyl)propionamides in reasonable yields (equation 51). No acylation of the enamine is observed. This reaction has been used as a key step in a new synthesis of 8-aza steroids (75JOC50). Cyclohexanone imines react in the same manner, except that the expected initial product cyclizes to give bicyclic lactams and enaminones (equation 52) (80T3047). 

Lithium aluminum hydride in ether readily reduces /3-propiolactones to 1,3-diols in fair to good yield. A recent application of this reaction is with the y-bromo-/3-lactone in equation (61), in which reductive cleavage of the bromine atom occurred simultaneously (78CC961). 

Synonyms-. Hydracrylic acid, 3-lactone 3-hydroxypropionic acid, lactone 3-hydroxypropionic acid, P-lactone propanol ide 3-propanolide propiolactone 3-propiolactone P-propionolactone... 

Reaction with propiolactone. The reaction of organocuprates with /Tpropio-lactone can be used to prepare -substituted propionic acids. 

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