Allylic ureas

Allyl urea Mercuric acetate Sodium chloride... 

To a refluxing solu tion of 100 g of allyl urea and 600 ml of absolute methanol there was added with stirring a suspension of 319 g of mercuric acetate and 600 ml of absolute methanol and 60 ml of glacial acetate acid complete solution resulted. After 6 hours of refluxing, the solution was cooled and clarified by filtration. To this solution there were added 50 g of sodium chloride and 240 ml of water. After a short time a heavy white precipitate settled out. This precipitate, which wes3-chloromercuri-2-methoxy-propylurea, was filtered, washed and dried. 

The nitrosation of A-alkylureas in dioxane-acetic acid mixtures is governed by the expression v = fc[HN02][urea], at fixed pH, and dependent on rate-determining proton transfer from the protonated iV-alkyl-iV-nitrosourea to acetate anion the order of reactivity, which reflects relative impediment by the alkyl groups, is as for nitrosation in aqueous media (methyl- ethyl- propyl- butyl- > allyl-urea). 

Reaction with allyl urea and methanol, followed by dilution with water and treatment with sodium chloride, precipitates methoxy(urea)propyhnercuric chloride, also known as chloromerodrin, a diuretic agent. 

Cyclizations of urea derivatives of allylamines with selenium reagents have been examined recently (equation 62 and Table 18).98 Cyclization of the allylic ureas produces franj-2-oxazoline derivatives with high stereoselectivity when the double bond is internal (Table 18, entry 2). Although O-methylisourea derivatives can be cyclized to dihydroimidazoles [see Section 1.9.3.2.2(ii)], cyclization with phenylsel-enenyl trifluoromethanesulfonate and trifluoromethanesulfonic acid produces 5,6-dihydro-1,3-oxazines (6-endo products), even when the double bond is monosubstituted (entry 3). 

Cyclization of allylic ureas. The reaction of C6H5SeCl (1) and silica gel with allylic ureas in CHC13 at 25° provides 2-oxazolines in 30-90% yield. The C6H5Se... 

This type of induced cyclization of allylic ureas carried out in the presence of silica gel affords imidazolines in good to excellent yields in a stereoselective manner. The utility of this procedure is illustrated by the formation of heterocycles 53 - 55 63. 

It may be prepared by the interaetion of N-allyl urea with mercurie aeetate in the presenee of methanol when the former gets aeetoxymereurated. The saturation also takes plaee simultaneously when the methoxy group is introdueed at position 2. Metathesis occurs on the addition of aqueous NaCl resulting in the precipitation of chlormerodrin which is subsquently filtered, washed and dried. 

A similar rearrangement apparentlv in transposed A-allyl ureas when the reaction is... 

Allyl capronate. See Allyl caproate Allyl caprylate. See Allyl octanoate Allylcarbamide. See Allyl urea Allylcatechol methylene ether. See Safrol Allyl chloride... 

Allyl undecylenate Allyl-2-undecylenate Allyl undecylenoate. See Allyl 10-undecenoate Allyl urea... 

Allylurea N-Allylurea. See Allyl urea 4-Allyl veratrole. See Methyl eugenol Aimoian HL. See Hydrogenated lanolin Almond alkyl amidopropyl dimethyl benzyl ammonium chloride. See Almondamidopropalkonium chloride Almondamide DEA CAS 124046-18-0... 

Monex . See Tetramethylthiuram monosulfide Monguard. See 6-(3,5-Dichloro-4-methylphenyl)-3(2H)-pyridazinone Monoacetina. See Glyceryl acetate Monoacetylcellulose. See Cellulose acetate Monoallylamine. See Allyl amine Monoallylurea. See Allyl urea Mono (2-aminoethyl) sulfate. See Aminoethyl sulfate... 

Urea, allyl-. See Allyl urea Urea, 1-allyl-2-thio-. See Allylthiourea Urea amidohydrolase. See Urease Urea, N-[1,3-bis (hydroxymethyl)-2,5-dioxo-4-imidazolidinyl-N,N -bis (hydroxymethyl)-. See Diazolidinyl urea Urea, butyl-. See N-Butylurea Urea, 1-(5-(t-butyl)-1,3,4-triadiazol-2-yl)-1,3-dimethyl-. See Tebuthiuron Urea, N -(3-chloro-4-methoxyphenyl)-N,N-dimethyl-. See Metoxuron Urea, N-(4-chlorophenyl)-N -[4-chloro-3-(trifluoromethyl) phenyl]-. See Cloflucarban Urea, N-(4-chlorophenyl)-N -(3,4-dichlorophenyl)-. See 3,4,4 -Trichlorocarbanilide... 

See Urea-formaldehyde resin, butylated Urea, polymer with formaldehyde and 1,3,5-triazine-2,4,6-triamine. See Urea/melamine/formaldehyde resin Urea, 2-propenyl-. See Allyl urea Urea, reaction prods, with butyl alcohol and formaldehyde. See Urea-formaldehyde resin, butylated Urease... 

Alkenyl succinic anhydride Allyl urea Aluminum nitrate Aluminum nitrate nonahydrate Amines, C18-unsaturated alkyl, dimers... 

Zinc undecylenate 557-11-9 Allyl urea 557-19-7 Nickel cyanide 557-20-0 Diethyl zinc 557-21-1 Zinc cyanide 557-27-7 Lupromag ... 

Zinc undecylenate 209-157-1 Allyl urea 209-161-3 Diethyl zinc 209-162-9 Zinc cyanide 209-166-0 Lupromag ... 

The corresponding intermolecular addition of cyclic ureas to terminal alkenes is catalyzed by Au[P(/-Bu)2(o-biphenyl)]Cl and AgOTf, and it provided alkylated ureas in high yield at 100 °C. The reaction even works with ethylene and other gaseous olefins. In the presence of chiral gold(I) pre-catalyst [Au2 (S)-3,5-r-Bu-4-MeO-MeOBIPHEP Cl2] and silver triflate, the hydroamination products were obtained with 71-76% ee (Scheme 4-68). Treatment of cyclic ureas with allylic alcohols in the presence of cationic gold(I) catalysts afforded allylated ureas with... 

Linear low-density polyethylene, LLDPE, was graft modified by incorporation of basic groups from, e.g., dimethylamino ethyl methacrylate, t-butylamino ethyl methacrylate, vinyl pyridine, or allyl urea. These copolymers were then used as reactive components for alloys with acidified polymers, viz., maleated polyolefins... 

Vilar and coworkers [59] have investigated the use of additives to suppress olefin migration in the self-metathesis of urea derivatives (Scheme 12.33). The Af-allyl urea 109 was found to undergo self-metathesis in the presence of Ru catalyst 3 in 33% yield. The isomerized species 110 was isolated as the major product (55% yield, Z= 1 1). Vilar and coworkers identified phenylphosphoric acid (112) as an effective inhibitor of the undesired alkene isomerization. When the metathesis of Af-allyl urea 109 was performed with phenylphosphoric acid (50mol%), the desired dimer 111 was isolated in 56% yield, and 30% of the starting material 109 could be recovered. The authors also investigated the use of benzoquinone derivatives, and found that 2,6-dichloro-l,4-benzoquinone (10 mol%) was equally... 

Unsaturated sulfonamides are recovered unchanged at temperatures normally required for ring closure and decompose at temperatures above 300 °C [669]. Allyl ureas decompose to give a large number of products [671]. Allyl urethanes react with hydrogenolysis of the C-N bond to form carbamates and a number of other products [671]. 

Seebach has published an account of the y-alkylation of the magnesium anion derived from the hindered allyl urea (20). Hydrolysis then liberates the aldehyde (Scheme 17). 

Another elegant example is the frans-selective reduction of lisuride (88) [67], reported by researchers at Sobering in the context of a synthesis of the partial dopamine receptor antagonist 89 (Equation 23) [68]. In this transformation, in situ deprotonation of the allylic urea side chain prevents its excision, which had been obsen/ed under catalytic hydrogenation conditions. 

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