Reaction with allylic acetates

There are also palladium-catalysed procedures for allylation. Ethyl 3-bromo-l-(4-methylphenylsulfonyl)indole-2-carboxylate is allylated at C3 upon reaction with allyl acetate and hexabutylditin[27], Ihe reaction presumably Involves a ir-allyl-Pd intermediate formed from the allyl acetate, oxidative addition, transmetallation and cross coupling. 

Eor reaction with allylic sulfides see (a) T. Takeda, S. Ogawa, N. Ohta, T. Eujiwara, Chem. Lett. 1987, 1967. For reaction with allylic acetates see (b) J. M. CuERVA, E. Gomez-Bengoa, M. Mendez, A. M. Eghavarren,/. Org. Chem. 1997, 62, 7540. 

Hydroxysulphenylation. The reaction of these two reagents in CH2Cl2/tri-fluoroacetic acid with allylic esters gives vic-trifluoroacetoxy sulfides, which are hydrolyzed to vic-hydroxy sulfides. The reaction with allyl acetate (equation I)... 

The research group of Trost has shown that stabilized enolates derived from -diesters and a-phe-nylsulfonyl esters are excellent nucleophiles for palladium(0)-catalyzed reactions with allylic acetates. Since these reactions involve ir-allylpdladium intermediates, they proceed with net retention of configuration and, therefore, differ from traditional displacement reactions where inversion is the rule. Moreover, the transition metal imposes a template effect on intramolecular versions of these reactions and... 

When prochiral nucleophiles are employed with more complex allyl electrophiles, there is the possibility of forming two sterocenters in the product (Scheme 32). For example, imino phosphonate 147 has been used as the nucleophile in the reaction with allyl acetate 4. The control of enantioselectivity at the benzylic position is very high, but there is lower relative stereocontrol at the newly formed stereocenter a to the phosphonate group.f ... 

Reaction with Allylic Acetates. The silylcuprate reacts with allylic acetates directly to give allylsilanes (eqs 16-18). Bis... 

Carbon-Heteroatom (N, S, O, Sn, Si, Se, P) Bond Formation. Primary and secondary amines (but not ammonia) undergo reaction with allylic acetates, haUdes, phosphates, and nitro compounds in the presence of Pd(PhsP)4 to provide the corresponding allylic amines (eq 26). A variety of ammonia equivalents have been demonstrated to be useful in this Pd(Ph3P)4-catalyzed alkylation, including 4,4 -dimethoxybenzhydrylamine, NaNHTs, and NaNs (eq 26). Both allylic phosphates and chlorides react faster than the corresponding acetates and (Z)-alkenes are isomerized to the ( )-isomers. The use of primary amines as nucleophiles in the synthesis of secondary allyl amines is sometimes problematic since the amine that is formed undergoes further alkylation to form the tertiary amine. Thus hydroxylamines have been shown... 

SCHEME 6 Proposed catalytic cycle for the Heck-Matsuda reaction with allyl acetates. 

Only a few practical applications of [ C]methyl phenyl sulfone have been reported so far (Figure 5.66). Representative ones illustrating the breadth of utility include reaction with allylic acetate in the presence of Pd(0) to give the respective 8,y-unsaturated derivative 244 as demonstrated with the synthesis of245 with ester 246 to furnish [ Cjmethyl ketone 24y203b sequential reaction of the dianion with a carbamate 12481 and an alkyl... 

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