2-butenyl phenyl

Atkinson and co-workers treated p-chlorophenyl 2-butenyl sulfide with 1,2-dihydro-2-quinolon-l-ylnitrene, and found two isomers in the product 76, between which equilibrium was reached by heating at 100°C for 30 min (121). The barrier was later determined to be 26.1 kcal/mol (122). A similar phenomenon was observed for the product obtained when 3-methyl-2-butenyl phenyl sulfide was used. However, the product (77) from /V-phthalimidonitrene afforded... 

Substituted allyl aryl ethers undergo a Claisen rearrangement similar to the reaction described in text Section 24.13 for allyl phenyl ether. 2-Butenyl phenyl ether rearranges on heating to give o-( 1-methyl-2-propenyl)phenol. 

Problem 18.10 What product would you expect from Claisen rearrangement of 2-butenyl phenyl... 

Operation of the insertion-elimination mechanism has been demonstrated in the reaction of rhodium hydride complex, RhHL4 (L=PPh3), with two isomeric allyl phenyl carbonates [56]. Unbranched 2-butenyl phenyl carbonate was found to give branched allylic phenyl ether exclusively, whereas the decarboxylation of the branched l-methyl-2-propenyl phenyl carbonate afforded unbranched 2-butenyl phenyl ether. These results can be accounted for by assuming a precata-lytic and catalytic insertion-elimination process as shown in Scheme 7. 

In the precatalytic process the rhodium hydride precursor undergoes insertion into the butenyl carbonate to form an alkylrhodium complex. (3-Elimina-tion yields 1-butene and phenylcarbonatorhodium complex. Upon decarboxylation a phenoxorhodium complex is produced that undergoes the SN2 type reaction with 2-butenyl phenyl carbonate to liberate the branched allylic ether, 1-... 

Hydroxy-2-[4-hydroxy-3- 3-methyl-2-butenyl)phenyl -6- 3-methyl-2-butenyI)-4Y -1 -henzopyran-4-one, 9CL 3 -Prenyllicoflavone A [91433-17-9]... 

Dihydroxy-5- 3-methyl-2-butenyl)phenyl -2-propenoic acid. 5-Prenylcaffeic acid Ci4Hi 04 M 248.278... 

Dihydroxy-2,5-bis(3-methyl-2-butenyl) phenyl]-1 -(2,4,6-trihydroxyphenyl)-2-propen-l-one, see P-20033... 

Dihydroxy-5-(3-methyl-2-butenyl) phenyl]-5,7-dihydroxy-6-(3-methyl-2-butenyl)-4/ -1 -benzopyran-4-one, see T-20058... 

Dihydroxy-3-(3-methyl-2-butenyl) phenyl]-7-hydroxy-5-methoxy-2/f-1 -benzopyran-2-one, see G-30005... 

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