Carbon monoxide oxime

Kondo and Watanabe developed allylations of various types of aldehydes and oximes by using nucleophilic (7r-allyl)ruthenium(ll) complexes of type 154 bearing carbon monoxide ligands (Equation (29)).345 These 73-allyl-ruthenium complexes 154 are ambiphilic reagents and the presence of the carbon monoxide ligands proved to be essential to achieve catalytic allylation reactions. Interestingly, these transformations occur with complete regioselectivity only the more substituted allylic terminus adds to the aldehyde. 

The carbon monoxide may be replaced by hydrogen cyanide (Gattermann) or by fulminic acid (in the form of mercury fulminate, Scholl), the first product then being respectively an imine or an oxime. 

Davis (Ref 23, p 408) stated that Wohler detd mol wt of NaF that corresponded to the single monomolecular formula of NaONC. This fact taken, together with the fact that MF warmed with coned aq H.C1 yields hydroxyl-amine, NHaOH, and formic acid proves that Fulminic Acid (qv) is the oxime of carbon monoxide ... 

The formula (V) attributed originally to fulminic acid, considers it to be an oxime of carbon monoxide [7] a more recent interpretation suggests the formula (Va) ... 

Sodium fulminate, soluble in water, has a molecular weight which corresponds8 to the simple monomolecular formula, NaONC. These facts, taken together with the fact that mercury fulminate warmed with concentrated aqueous hydrochloric acid yields hy-droxylamine and formic acid,9 prove that fulminic acid is the oxime of carbon monoxide. 

Closer inspection of oxime formation from the stable 2,4,6-trimethylacetophenone imine revealed the N-oxygenating activity to be sensitive to the presence of proto-typic inhibitors of the P-450 system, such as carbon monoxide, SKF 525A and DPEA1. 

Radical chemistry has witnessed remarkable progress since the mid 1980s [1], In addition to common radical C2 synthons such as alkenes and alkynes [2], several radical Cl synthons are also available, including carbon monoxide, isonitriles, and sulfonyl oxime ethers [3, 4]. As featured in Scheme 6.1, a variety of combinations of radical Cl and C2 synthons are now possible, which makes radical methodologies more attractive and permits the design and implementation of a wide range of multicomponent processes. 

The combination of carbon monoxide with sulfonyl oxime ethers allow for a set of multicomponent coupling reactions involving consecutive Cl/Cl-type coupling, a rare class of radical multicomponent reactions. In Scheme 6.27, examples of three-, four-, and five-component coupling reactions are shown [46], In these reactions, allyltin is not incorporated into the product, but serves as an acceptor of the phenylsulfonyl radical and a source of the tributyltin radical, which delivers the radical chain. 

Fulminic Acid or Paracyanic Acid (Oxime of Carbon Monoxide) (Knallsaure in Ger Acide fulminique in Fr Gremuchaya Kislota in Russ), HONCC mw 43.03, N 32.56%, OB to C02 —55.8%. Known in solution, forms variously expl metallic salts known as fulminates. The mercury salt, apparently the first discovered was formed by the action of mercuric nitrate on ethyl alcohol (Ref 2). The free acid can be isolated in cold ether and below —5° may exist as a gas for a short time. When heated it polymerizes to meta-fulminuric acid, HC.C(=NOH)C(=NOH)O.N. Other methods of... 

The diazepine 85 (tetramethyleneurea) has been prepared by a variety of routes. Among these are the treatment of tetramethylene diisocyanate with water,70-72 the rearrangement of the oxime (86) in polyphosphoric acid,73,74 and the reaction of 1,4-diaminobutane with sulfur, methanol, and carbon monoxide at high pressure.75 A novel preparation of 85 involves the reaction of 1,4-diaminobutane with 87 to give the silylated diamine (88). Reaction of 88 with phosgene and triethylamine yielded the bistrimethylsilyldiazepine (89) which was then hydrolyzed in aqueous ethanol to give 85.76... 

Fuhninic acid, C=N H C=N-OH, is a divalent carbon derivative hke carbon monoxide it is formally an oxime of carbon monoxide. Free fuhninic acid is unstable, but the explosive mercury salt, which is used as a detonator, is obtained by treatment of elemental mercury with a mixture of ethanol and lutric acid. The fulminate ion, C=N-0, like carbon monoxide and cyanide ion, functions as a strong-field... 

Reaction of complex (90) with methyllithium followed by acid and carbon monoxide affords a mixture of acylated complexes (Scheme 149). Reaction of an oxime complex with organocuprates followed by acetic anhydride, carbon monoxide, and potassium carbonate gives meta-acylaniline derivatives (Scheme 150). In both cases, the nucleophile probably initially adds to the metal followed by an acyl transfer. 

Up until the end of the 1980s, radical carbonylation chemistry was rarely considered to be a viable synthetic method for the preparation of carbonyl compounds. In recent years, however, a dramatic change has occurred in this picture [3]. Nowadays, carbon monoxide has gained widespread acceptance in free radical chemistry as a valuable Cl synthon [4]. Indeed, many radical methods can allow for the incorporation of carbon monoxide directly into the carbonyl portion of aldehydes, ketones, esters, amides, etc. Radical carboxylation chemistry which relies on iodine atom transfer carbonylation is an even more recent development. In terms of indirect methods, the recent emergence of a series of sulfonyl oxime ethers has provided a new and powerful radical acylation methodology and clearly demonstrates the ongoing vitality of modem free radical methods for the synthesis of carbonyl compounds. 

Very recently, Kim and co-workers have reported a new useful radical acylation approach which uses a series of sulfonyl oxime ethers, some of which function as a viable radical Cl synthon. Unlike carbon monoxide and isonitriles, which operate as a radical acceptor/radical precursor type Cl synthon, sulfonyl oxime ethers... 

B. Carbon Monoxide-Mediated Deoxygenation of Oximes and Nitro Compounds... 

Choi IS, Kim SK, Lee SS, et al Evaluation of outcome of delayed neurologic sequelae after carbon monoxide poisoning by technetium-99m hexamethylpropylene-amine oxime brain single photon emission computed tomography. Eur Neurol 35 137-142, 1995... 

The radical carbonylation of an alkyl iodide in the presence of Kim s sulfonyl oxime ethers [58, 59, 60] provides a new type of multicomponent coupling reaction where plural radical Cl synthons are consecutively combined [61]. In the transformation, allyltin was used to serve as a trap of benzenesulfonyl radical which converts sulfonyl radical to a tin radical, thus creating a chain. Scheme 14 illustrates such an example, where the product was easily dehydroxylated to give the corresponding tricarbonyl compound on treatment with zinc/AcOH. The radical acylation reaction by Kim s sulfonyl oxime ethers can be conducted under irradiation with the addition of hexamethylditin. This is an alternative path for achieving a similar transformation without the use of photolysis equipment. Scheme 15 illustrates several examples where carbon monoxide and Kim s sulfonyl oxime ethers are successfully combined to create new tandem radical reaction sequences [61],... 

Very closely related to decarbonylation of an -hydroxy acid is the Wohl degradation, in which an -hydroxy aldehyde is degraded to the aldehyde with one fewer carbon atoms. This starts from the oxime, which is converted by removal of water into the hydroxy nitrile, whence elimination of hydrogen cyanide — analogous to that of carbon monoxide and water from an -hydroxy acid — affords the lower aldehyde ... 

A number of modern industrial processes are based on the catalytic carbonyl at 1 on of organic substrates by carbon monoxide. ll In contrast, the application of carbon monoxide as reductant in organic synthesis is confined to relatively few exampl es. 2l In recent years the catalytic carbonyl at I on of nitro compounds has become a ery intense field of research. This is due to the fact that 3 series of industrially important compounds can be obtained - om nitro compounds and carbon monoxide in a single step azo compounds, amides, amines, oximes, ureas, urethanes and isocyanates [ 3] and indoles. Ureas and urethanes are important final products and intermediates in the synthesis of ert ll eps and pesticides. On the other hand mono and di-1 socyanates are very important intermed 1 a es in the manu-i-acture of pesticides, polyurethane foam plastics, synthetic leather, adhesives and coatings. 

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