Propiolactone Treatments

The reaction of (3-propiolactone with fiber can be catalyzed by acids or bases to yield two different products. Treated wood in acidic conditions with 30% WPG resulted in good decay resistance and anti swelling efficiency (ASE) of 60%. Nevertheless a strong degradation of wood has been observed [40]. 

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Influenza (inactivated by formaldehyde or propiolactone treatment), hepatitis A (inactivated by formaldehyde tteat-ment), pertussis (inactivated by formaldehyde tteatment, usually combined with diphtheria and tetanus toxins into a single vacdne), rabies, tick-borne encephalitis (formaldehyde inactivated). 

What is the structure of the polymer produced by treatment of /3-propiolactone with a small amount of hydroxide ion ... 

Treatment with formaldehyde or acetone Treatment with phenol or phenol and heat Treatment with propiolactone... 

Among the various chemicals to form ether bonds with hydroxyl groups in wood, a high decay resistance of wood treated with P-propiolactone [25] and acrylonitrile [26,27], both at 25% WPG, has been reported earlier. However, an undesirable carcinogenic effect in (J-propiolactone as well as loss of impact strength and low ASE in acrylonitrile-treated wood discouraged further works on these treatments [7]. 

Recently, a series of works have been published on the cationic po merization of lactones (e.g. p-propiolactone and e-caprolactone ) and various ionic ecies have been reported together with elaborate kinetic treatments and some electrochemical measurements. In our opnion the chemical structure of the growing species in the cationic polymerization of lactones has not yet firmly been established (see also Ref. 190) and, therefore, a more detailed discussion of the% interesting and important systems must wait until these structures are known. 

Treatment of 2-methylthioimidazoline (653) with /3-trichloromethyl-j8-propiolactone (654) produced (655), presumably by initial iV-acylation and then cyclization to form the oxazine ring (69JOU1790). 

The Potassium complex of I8-Crown-6 or Potassium Naph-thalenide effects ring-opening to give acetates or their alkylated derivatives in good yield (eq 3). Treatment of the reaction mixture obtained from p-methyl-p-propiolactone and potassium-18-crown-6 with hydrochloric acid or alkyl halides gives the acetate (S) or its alkylated derivative (6), respectively. The a,3-unsaturated carboxylic acid (7) or its ester (8) is formed by the action of the potassium naphthalenide-18-crown-6 complex. ... 

Titanium Lewis acids effect formal [2 + 2] cycloaddition as shown in Eqs (158) [401] and (159) [402,403]. Subtly changing the reaction conditions and substrates alters the product of Eq. (159) from the cyclobutane to a dihydrobenzofuran derivative, as will be described below. The analogous hetero [2 + 2] addition of a chiral aldehyde to a silylketene proceeded stereoselectively in the presence of titanium tetrachloride to give the propiolactone, as shown in Eq. (160) [404]. The silyl group was removed by the treatment with KF. 

Treatment of jS-propiolactone with base gives a polymer. Give a likely structure for this polymer, and show a likely mechanism for the process. Is this an example of chain-reaction or step-reaction polymerization ... 

Enzyme-linked immunoabsorbent assays (ELISAs) for VHP infections can be performed on samples inactivated by treatment with P-propiolactone. Reverse transcriptase polymerase chain reaction (RT-PCR) tests on samples following RNA extraction using chloroform and methanol can detect most of the VHP agents rapidly. RT-PCR is particularly useful when isolation of the virus is difficult or impractical, and was effective in detecting the agent causing HPS months before it was isolated in culture (48). 

H- 2] Cycloaddition is one of the most convenient methods for the construction of optically active four-membered carbon- or heterocyclic rings that are useful intermediates in organic synthesis. Titanium Lewis acids have been found to promote formal [2 + 2] cycloaddition between two olefins with different electronic features [181]. The analogous hetero [2 + 2] addition of a chiral aldehyde to a silylketene can be catalyzed by TiCU to give the propiolactone with high diastereoselectivity as shown in Scheme 14.80. The silyl group in the product can be easily removed by treatment with KF [182]. 

Treatment of /3-ethynyl-0-propiolactone (165) with alkyl, aryl, or vinyl Grignard reagents in the presence of a catalytic amount of copper(i) iodide affords high yields of alka-3,4-dienoic acids (166). ... 

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