Ritter reaction rearrangement

Other sequences that transform primary alcohols to primary amines include (a) conversion of the alcohol to a cyanate, rearrangement to an isocyanate, and hydrolysis,3 and (b) conversion of the alcohol to an -V alkylformamide via the Ritter reaction, followed by hydrolysis.4... 

Under Ritter reaction conditions the cycloocta-1,5-diene 392 is prone to undergo trans-annular cyclization into cA-bicyclo[3.3.0]octane derivatives (equation 141)194. Norbor-nadiene 393 and 5-ethylidenenorbomene 394 rearrange under the same conditions to... 

Under the Ritter reaction conditions above described, the sesquiterpene (—)-cariophyllene oxide undergoes an interesting rearrangement, originating an A-acyl amino clovane-type compound, in 33% yield, after purification by flash chromatography (Scheme 21) [92]. 

Although terminal alkenes provide the best yields, the Ritter reaction is also successful when using tri-substituted alkenes and haloalkenes. Markovnikov addition is generally observed. Rearranged products arise occasionally, especially with alkenes that are prone to cationic rearrangements (equation 165).233... 

The Ritter reaction of internal alkenes may yield mixtures of regioisomers, and on occasion, small amounts of rearranged products (equation 166).234... 

We wish to report a new approach to condensation reactions of hydroxy compounds related to the Ritter reaction, the Beckmann rearrangement and peptide formation based on easily accessible pentaco-ordinate spirophosphoranes of the type (3) (6 - ). 

Alkyl iodides are cleaved in acetonitrile/lithium perchlorate to iodine and al-kyl.cations. These react prior to or after rearrangement in a Ritter reaction with acetonitrile to form N-alkylacetamides in 21% to 75%yield (Eq. (217) ) 4S8). 

In the Ritter reaction a rather different kind of evidence for the cation is the fact that families of isomeric alcohols all give the same product. In all these cases, rearrangements of the first formed carbocation (Chapter 37) can easily account for the products. Another example in the decalin series is this Ritter reaction with KCN as the nitrile in acidic solution so that HCN is the reagent. The starting material is a spirocyclic tertiary alcohol but the product is a frans-decalin formed by... 

The reaction differs from the Ritter reaction by the two types of electrophilic activation of the reagents and by the two types of rearrangement of nitrilium 285 and carboxonium ions 288 (equation 94). Besides, this interaction proceeds at an oxidation level of two, while the Ritter reaction occurs at an oxidation level of one17. While it may be shown that A-acyliminium ions 365 can be obtained from a carbonyl compound and a nitrile via the Ritter reaction, then it is only the second step b) in a three-step process where the first step (a) is the reduction of carbonyl compound 364 to alcohol 366 and the third step (c) is an oxidative dehydrogenation of amide 369 obtained3 (equation 105). 

A combination of the Pummerer rearrangement and the Ritter reaction occurs in the reaction of acetonitrile with methyl phenyl sulfoxide (equation 25) in a mixture of irifluoroacetic acid and its anhydride, although a substantial amount of the nonnal a-acetoxylation also occurs. Participation by amido groups is also possible, the interest here being largely in the construction of lactams via the intramolecular cycli-zation mode. Whereas Wolfe and his coworkers were unable to find conditions for the cyclization of S-phenylcysteinamide sulfoxides under Pummerer conditions, Kaneko found that variously substituted... 

The Pinner reaction is the standard method of preparing imidate salts (the free imidate is obtained upon basification with weak bases) by alcoholysis of nitriles in the presence of mineral acids. However, this method is not suitable for the synthesis of allylic imidates since, under these reaction conditions, allylic amides, the product of the Ritter reaction, are formed. The acetimidates are easily prepared by condensation of the sodium or potassium alcoholate with trichloro- or trifluoroacetonitrile in high yield. For the rearrangement reaction the crude imidates can be used. 

The conversion of 2,5-pyridinedicarboxylic acid Af oxide (284) inaceto-nitrile/acetic anhydride to the corresponding 6-amino-nicotinic acid (288) seems to be a Ritter reaction of intermediate cation 285 with acetonitrile, followed by rearrangement of intermediate 286 to 287, which is then saponified by potassium hydroxide to give 49% of 6-aminonicotinic acid (2M) and 8% of 6-hydroxynicotinic acid (289) (83EUP90I73). 

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