Low-valent titanium-mediated cyclopropanation of vinylogous esters

[reaction: see text] Inter- and intramolecular titanium-mediated cyclopropanation reactions of vinylogous esters are reported. Comparison between the Kulinkovich cyclopropanation of esters and vinylogous esters provides mechanistic insight regarding reaction variables such as reaction temperature, solvents, and a Lewis acid additive.     

Gold-catalysed allylic alkylation of aromatic and heteroaromatic compounds with allylic alcohols

Friedel-Crafts allylic alkylation of a wide variety of aromatic and heteroaromatic compounds with allylic alcohols catalysed by AuCl(3) (5 mol%) under mild conditions at room temperature was accomplished in good to excellent yields (up to 99%) and regioselectivity.     

Gold- and silver-catalyzed allylic alkylation of 1,3-dicarbonyl compounds with allylic alcohols

A highly efficient gold- and silver-catalyzed allylic alkylation of 1,3-dicarbonyl compounds with allylic alcohols has been developed. The reaction was shown to proceed expediently for a wide variety of 1,3-dicarbonyl compounds and allylic alcohols, including 1° and terminal ones, under very mild conditions at room temperature in good to excellent yields (55-96%).     

Efficient and stereoselective synthesis of allylic ethers and alcohols

[Structure: see text] A short and efficient synthesis of allylic TBS ethers and allylic alcohols has been developed, based upon a unique Kocienski-Julia olefination reaction. Allylic alcohols and allylic ethers are obtained in good to excellent yields and with high (E)-selectivity. The conditions are mild and the procedure is broadly applicable.     

Iodine-catalyzed allylic alkylation of sulfonamides and carbamates with allylic alcohols at room temperature

A highly efficient iodine-catalyzed allylic alkylation of a wide variety of sulfonamides and carbamates with allylic alcohols is reported herein. The reaction is operationally straightforward and proceeds under very mild conditions at room temperature in good to excellent yields (up to 99%).     

Improved synthesis of isocarbacyclin using regioselective alkylation of allylic alcohols

Two efficient syntheses of isocarbacyclin (1) have been realized using highly regioselective direct alkylation of both - and -allylic alcohols (2 and 3)     

trans-hydroalumination/alkylation: one-pot synthesis of trisubstituted allylic alcohols

[reaction: see text] Described herein is a method of stereoselective synthesis of trisubstituted allylic alcohols by alkylation of alkenyl alanates, formed in situ through treatment of propargyl alcohols with Vitride (Red-Al). This technique represents the first of its kind to feature a trans-hydrometalation, and is particularly effective for the formation of 1,4-dienes. Applications involving primary, secondary, and tertiary alcohols are discussed, as well as limitations regarding both alkyne and electrophile components.     

Pd.Et3B-catalyzed alkylation of amines with allylic alcohols

A combination of catalytic amounts of Pd (0.05 mmol) and Et3B (0.3 mmol) promotes allylic alkylation of primary and secondary aromatic and aliphatic amines (1.0 mmol) by the direct use of allylic alcohols, providing tertiary amines in excellent yields under mild conditions (room temperature approximately 50 degrees C).     

Highly stereoselective Luche reduction of α-enonesulfoxides to 2-sulfinyl allylic alcohols

Luche reduction of α-enonesulfoxides with NaBH₄ in methanol in the presence of YbCl₃ afforded 2-sulfinyl allylic alcohols in high yields and with excellent diastereoselectivity.     

The role of trimethylsilyl group in highly stereoselective eposidation of allylic alcohols

The epoxidation of allylic alcohols carrying Me₃Si group on the double bonds with VO(acac)2-tBuOOH or MCPBA provides erythro or threo epoxy alcohols, respectively with high stereoselectivity.     

A stereoselective synthesis of β,γ-disubstituted allylic alcohols of z-configuration

Reaction of alkyllithiums $\text{1}$ with isoprene epoxide $\text{2}$ gives β,γ-disubstituted allylic alcohols $\text{3}$ of Z-configuration. The reaction of π-lithiotricyclene as alkyllithium gives α-santalol $\text{5}$, which is one of the main constituents in East Indian sandalwood oil.     

Regioselective and asymmetric allylic alkylation of vinyl epoxides for the construction of allylic alcohols via synergistic catalysis

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed,which exhibits good functional group compatibility,high atomic and step economy.This protocol utilizes a strategy of synergistic catalysis with a chiral N,N’-dioxide/Ni^Ⅱ complex and an achiral Pd⁰ catalyst,generating a series of multisubstituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-,Z/E-and enan...     

Pd-catalyzed nucleophilic allylic alkylation of aliphatic aldehydes by the use of allyl alcohols

Under catalysis of Pd(OAc)₂-(P-n-Bu)₃, Et₂Zn promotes a variety of allyl alcohols to undergo nucleophilic allylation of aliphatic aldehydes and ketones at room temperature and provides homoallyl alcohols in 60-90 and ca. 60% isolated yield, respectively. The reaction is irreversible and kinetically controlled, and unique regio- and stereoselectivities observed for the allylation with unsymmetrically substituted allyl alcohols are discussed.     

Kinetic resolution of allylic alcohols via stereoselective acylation catalyzed by lipase PS-30

By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic allylic alcohols has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 968. Substituent effect is briefly discussed.     

Addition/elimination reactions of ethylsulfonyl pyridines: stereoselective synthesis of vinylpyridine allylic alcohols

2-(Phenylsulfonyl)ethyl pyridines can be coupled with aldehydes leading directly to sulfone-eliminated vinylpyridine allylic alcohols. These products are obtained in good yield and with high levels of stereocontrol.     

Pd-catalyzed allylic alkylation of thioamides

This work describes the first Pd-catalyzed allylic alkylation of thioamides. Various thioamides were efficiently α-allylated in high yields and with excellent selectivity for monoallylation under mild reaction conditions. The process not only provides a facile method for the synthesis of functionalized thioamides, but also presents a useful transformation for synthetically important thioamides.