Rearrangement reaction with amines

This result is consistent with an equilibrium between an initially formed a-substituled allyl tellnroxide (resulting from the well-known regio-controlled electrophilic attack at the y-carbon) and the y-isomer (which is really the main product, as detected by NMR). In the snbseqnent reaction with amines, the more nucleophilic alkylamines attack the central carbon atom, giving rearranged products, whereas the less nucleophilic arylamines attack the terminal carbon, giving the thermodynamic y-product. 

Sodium cyanide in DMF at 120 °C has been used for the decarboxylation of 1-substituted-4-oxoquinoline-3-carboxylic acids <94TL(35)8303>. Quinoline Reissert adducts have been epoxidized at the 3,4-bond. Its reaction with amine nucleophiles gave regiospecifically substituted 1,2,3,4-tetrahydroquinolines <95H(41)897>. Successive Claissen rearrangements of 2-(8-quinolinoxymethyl)-3-(8-quinolinoxy)-l-propene gave a product which shows excellent ability to extract heavy metal ions <95TL(36)5567>. An Eschenmoser approach has been used in a facile synthesis of monofunctional and difunctional A -substituted-4-alkylidenequinolines (54) (Scheme 39) <95S(St)56>. 

Amadori rearrangement of, 211 biochemical activity of, 212 reaction with amines, 209 —l,2,3-tri-0-acetyl-4-benzamido-4-de-oxy-L-, 182... 

Substitution of CO by phosphines 145 The Dotz reaction 149 Rearrangement reactions with loss of CO 151 Photochemical reactions 153 Reactions at the carbene carbon 158 General features 158 Amine nucleophiles 159 Phospine and phosphite nucleophiles 167 Alcohols and alkoxide ion nucleophiles 171 Thiol and thiolate ion nucleophiles 179 Intramolecular nucleophilic reactions 191 Hydroxide ion and water as nucleophiles 194 Insertion reactions initiated by nucleophilic attack Acid-base reactions at the a-carbon 207 General features and methods 207 Kinetic and thermodynamic acidities 209 Effect of structure on pKa values 210 Intrinsic rate constants for proton transfer 219 Thermodynamic acidities in organic solvents 223 Hydrolysis of ionizable carbene complexes 228 Acknowledgments 232 References 233... 

Schaumann and his group [88-91] disclosed that thioketenes are efficiently produced by rearrangement of (silylethynyl) vinyl sulfides (R = SiMe,) under mild conditions (Scheme9.15). The products can be trapped by amines, providing y-un-saturated thioamides. In the absence of the silyl group, thioketenes could not be isolated, but were converted in thioamides by reaction with amines [92]. 

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