N-Vinyl lactams

An additive described as reducing the water loss and enhancing other properties of well-treating fluids in high-temperature subterranean environments consists of polymers or copolymers from N-vinyl lactam monomers or vinyl-containing sulfonate monomers. Organic compounds like lignites, tannins, and asphaltic materials are added as dispersants [175]. 

Polymers or copolymers from N-vinyl lactam monomers or [175]... 

Polymer from N- Vinyl Lactams and Vinyl Sulfonates. A water-soluble polymer from N-vinyl lactam monomers or vinyl-containing sulfonate monomers... 

To provide a prolonged and controlled drug release to the surface of wounds or bums, the material may contain two or more microfiber layers. Different layers may have different compositions. Each layer includes the biodegradable polymer with or without poly(N-vinyl)lactam. The layers may also have different biodegradable polymers (78). 

In order to improve the adhesiveness of a UV curable ink composition to a recording medium, a radiation curable inkjet ink composition that uses N-vinyl lactam has been proposed. 

However, there are concerns that N-vinyl lactams, such as N-vinyl caprolactam, may generate surface tackiness of the cured ink images or cause leaching (7). This arises since N-vinyl caprolactam does not readily copolymerize with acrylate monomers that are used in the composition (8). 

Other monomers that copolymerize with alkyl vinyl ethers are vinyl ketones [47], acrolein diacetate [48], acrylamide [49], alkoxy 1,3-butadienes [50], butadiene [51], chloroprene [52], chlorotrifluoroethylene [53], tri-and tetrafluoroethylene [54], cyclopentadiene [55], dimethylaminoethyl acrylate [56], fluoroacrylates [57], fluoroacrylamides [58], A-vinyl car-bazole [59,60], triallyl cyanurate [59,60], vinyl chloroacetate [61,62], N-vinyl lactams [63], A-vinyl succinimide [63], vinylidene cyanide [64, 65], and others. Copolymerization is especially suitable for monomers having electron-withdrawing groups. Solution, emulsion, and suspension techniques can be used. However, in aqueous systems the pH should be buffered at about pH 8 or above to prevent hydrolysis of the vinyl ether to acetaldehyde. Charge-transfer complexes have been suggested to form between vinyl ethers and maleic anhydride, and these participate in the copolymerization [66]. Examples of the free-radical polymerization of selected vinyl ethers are shown in Table IV. 

Azadienes undergo Diels-Alder reactions to form pyridine, dihydro- and tetrahydropyridine derivatives. N-Vinyl lactim ethers undergo Diels-Alder reactions with a limited set of dienophiles. " Thioketones react with dienes to give Diels-Alder cycloadducts. The carbonyl group of lactams have also been shown to be a dienophile. Certain heterocyclic aromatic rings (among them furans) can also behave as dienes in the Diels-Alder reaction. Some hetero dienes that give the reaction are -C=C-C=0, 0=C-C=0, and N=C-C=N. ... 

This method for preparing 2-phenyl-1-pyrroline, and assorted 2-substituted 1-pyrrolines, is one of the best currently available, particularly because it reproducibly affords clean materials. Generally, the procedure is amenable to various aromatic esters 2 it has also been applied successfully to aliphatic esters (Table I).3 An advantage of this method is the use of readily available, inexpensive N-vinyl-pyrrolidin-2-one as a key starting material. This compound serves effectively as a 3-aminopropyl carbanion equivalent. The method illustrated in this procedure has been extended to include the synthesis of 2,3-disubstituted pyrrolines. Thus, alkylation of the enolate of the intermediate keto lactam, followed by hydrolysis, leads to various disubstituted pyrrolines in good yields (see Table II).3... 

N-Vinylation. Imides and lactams are converted to N-vinyl derivatives when heated with vinyl acetate in the presence of Na2PdCl4. 

Janssen et al. [144] focused their work on ozonization of polyvinyl lactam, grafting with hydrophilic methacrylic monomers for applications in the field of contact lenses and other products used in the medical domain. The most studied polymer remains the poly-N-vinyl pyrrolidone which is ozonized either in solid state or in aqueous solution. This activation step leads to three hydroperoxides per chain but also to chain scissions. The resulting product is formulated with different mixtures of methacrylic and dimethacrylic monomers to graft them onto activated polymer by UV initiation. Using dimethacrylic monomers lead to perfect cross-linked polymers presenting excellent resistance to solvents. Unfortunately, the mechanisms of action of ozone onto polyvinyl lactams do not seem to have been studied in detail. 

Reppe and coworkers644 described the N-vinylation of amides and lactams by acetylene. The amide and one percent by weight of potassium were heated in an autoclave at 140-160 °C in an acetylene-nitrogen atmosphere. A method to produce selectively either the E- or the Z-isomers has been described645. 

Phosphorus-containing enamines have been prepared by phosphorylation of N-vinyl substituted tertiary amides, lactams and cyclic imides with phosphorus pentachloride ". Addition of amines to diphosphoryl alkynes has been described. Addition of RR NH [R = H, Ri = Me, cyclohexyl, PhCH2 RR = (CHj) to (Et0)2P(0)C=CP(0K0Et2)2 in CH2CI2 at 25 °C gave 93-100% of (Et0)2P(0)C(NRRi)=CHP(0)(0Et2)2 . Speziale and coworkers have studied the reactions of phosphorus compounds with trichloroacetamides. 

Similarity, compound 207 was thermally cyclized to give 216 and 217. The latter, 217, was converted into 218 and 219 in 72 and 11% yield, respectively (Scheme 21). ° The major one was sequentially debenzylated and diacylated to give 220, which was converted to the iodo derivative 221, followed by exposure to zinc in boiling ethanol to allow concurrent reductive ring cleavage, N-deprotection and cyclization to afford the vinyl lactam 222 in a diastereoisomerically pure state. Ozonolysis of 222 followed by reduction with sodium borohydride and then further reduction with LiAlH4 afforded (-l-)-31. On the other hand, the minor isomer 219 afforded the (-l-)-platynecine [(- -)-30] by following similar steps. 

Synonyms 1-Ethenyl-2-pyrrolidinone homopolymer 1-Ethenyl-2-pyrroli-dinone polymers Poly 1-(2-oxo-1-pyrrolidinyl) ethylene] Polyvidone Polyvidonum Poly (n-vinylbutyrolactam) Po (1-vinyl-2-pyrrolidinone) homopolymer Polyvinylpyrrolidone Povidone PVPP N-Vinylbutyro-lactam polymer 1 -Vinyl-2-pyrrolidinone polymer Vinyl pyrrolidone homopolymer N-Vinylpyrrolidone polymer... 

An improved method that can be easily scaled-up has been developed for the preparation of benzyl-N-vinyl carbamate 810 (Z-vinylamine), a valuable synthetic intermediate in the synthesis of p-lactam antibiotics [589]. In this method, vinyl isocyanate 809, formed by the Curtius rearrangement of acryloyl azide 808, is codistilled with a solvent such as toluene into benzyl alcohol containing a catalyst and an inhibitor. The product thus obtained can be purified by crystallization, thereby avoiding purification by high-vacuum distillation or chromatography. Potential safety issues associated with the process are important [590, 591]. 

Although N-vinyl compounds are the starting materials for the synthesis of several important polymers, a convenient and general method of synthesis is not known. In the presence of catalytic amounts of NaPdCU, however, cyclic iV-vinyl compounds are formed in good yield (ca. 80%) by the reaction of imides and lactams with vinyl acetate [equation (20)]." ... 

Cheung, L. L. W., Yudin, A. K. (2010). Synthesis of highly substituted cyclobutane fused-iing systems from N-vinyl beta-lactams through a one-pot domino process. Chemistry - A European Journal, 16, 4100-4109. 

Abstract Some newly developed methods for assembling N-containing heterocycles are summarized here. The key transformations in these methods are Pd- or Cu-catalyzed N-arylation and N-vinylation. The heterocycles include indoles, benzimidazoles, pyrroles, indazoles, indolines, lactams, quinazoUnones and heterobenzazepines. These conceptually-novel and rehable methods should find applications in the synthesis of bioactive compounds and material molecules. 

If a bromomethyl- or vinyl-substituted cyclopropane carbon atom bears a hydroxy group, the homoallyiic rearrangement leads preferentially to cyclobutanone derivatives (J. Sa-laun, 1974). Addition of amines to cydopropanone (N. J. Turro, 1966) yields S-lactams after successive treatment with tert-butyl hypochlorite and silver(I) salts (H.H. Wasserman, 1975). For intramolecular cyclopropane formation see section 1.16. 

The reaction can be done intramolecularly. N-Benzyl pent-4-ynamide reacted with tetrabutylammonium fluoride to an alkylidene lactam. Similar addition of a tosylamide-alkene, with a palladium catalyst, led to a vinyl Al-tosyl pyrrolidine. Similar cyclization reactions occur with tosylamide-alkynes. ... 

Radical cyclization is compatible with the presence of other functional groups. Treatment of XCH2CON(R)-C(R )=CH2 derivatives (X = Cl, Br, 1) with Ph3SnH and AIBN led to formation of a lactam via radical cyclization. " Cyclization of N-iodoethyl-5-vinyl-2-pyrrolidinone led to the corresponding bicyclic lactam, " and there are other examples of radical cyclization with molecules containing a lactam unit " or an amide unit. Radical cyclization occurs with enamines as well. Photochemical irradiation of A,A-dialIyl acrylamide leads to formation of a lactam ring, and in this case thiophenol was added to generate the phenylthio derivative. Phenylseleno N-allylamines lead to cyclic amines. co-Iodo acrylate esters cyclize to form lactones. " ... 

A somewhat unusual sequence to generate azepanones 80 involved the intramolecular addition of hydroxylamines to alkynes 76 to form cyclic nitrones 77. A vinyl magnesium bromide addition at low temperatures and a reduction with TiCls followed by N-Boc protection led to the azepane 78. Double bond bromination and subsequent RUO4 oxidation gave the lactam 79. Several further steps allowed the generation of the lactam structure 80 proposed for d,/-aca-cialactam, but the spectral data of the synthetic material differed from that of the natural product (Scheme 16)] [23 a, b]. 

Microwave-induced organic reaction enhancement chemistry was used for the hydrogenolysis of the C-N bond in lactams. To a solution of a-vinyl (3-lactams in ethylene glycol were added HC02NH4 and 10% Pd/C catalyst then this mixture was irradiated in a microwave oven (Scheme 4.108).357... 

A similar approach was used by the Alcaide group [183] in the synthesis of tricyclic (3-lactams 6/1-391 from 6/1-390 (Scheme 6/1.99). In this domino process the primarily obtained it-allyl-Pd-complex reacts with the N-nucleophile of the urethane moiety to form a C-N-bond and a vinyl halide. The final step is then an intramolecular Heck-type reaction of the vinyl halide with the alkyne moiety and re-... 

A report on a regiospecific 6-exo radical cyclization for the generation of lactams 173 highlights a remarkable halogen-substitution effect on the direct reactions of unsaturated N-H amides on vinylic halogen substituents <06OL2647>. 

Most of the work on the C-N bond-forming crosscoupling reactions has concentrated on the formation of aromatic C-N bonds. Recent studies show that the application of cross-coupling reactions to alkenyl halides or triflates furnished enamines (Scheme 19) (for palladium-catalyzed reaction, see 28,28a-28d, and for copper-catalyzed reaction, see 28e-28g). Brookhart et al. studied the palladium-catalyzed amination of 2-triflatotropone 109 for the synthesis of 2-anilinotropone 110.28 It was found that the reaction of 109 proceeded effectively in the presence of racemic BINAP and a base. As a simple method for the synthesis of enamines, the palladium-catalyzed reactions of alkenyl bromide 111 with secondary amine were achieved under similar conditions.2841 The water-sensitive enamine 112 was isolated as pure compound after dilution with hexane and filtration through Celite. The intramolecular cyclization of /3-lactam 113, having a vinyl bromide moiety, was investigated by Mori s... 

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