铟促进的烯丙基硒醚的合成

烯丙基溴和炔丙基溴在铟促进下与二硒化合物反应，生成烯丙基和炔丙基硒醚。反应无需严格的无水无氧条件，烯丙基溴以α-位与二硒化合物反应，产率55%～91%。     

Application of the intramolecular isomerisation-aldolisation from allylic alcohols and allylic silyl ethers to the synthesis of indanones and indenones

A new access to indanones was discovered through a one-step nickel or iron-mediated transposition of 2-hydroxyisobenzofurans. Starting from the corresponding silylenol ethers, a new one-pot tandem isomerisation-Mukaiyama aldol process was also developed. These versatile strategies will be useful for the preparation of various types of indanones and indenones.     

Copper(II)-catalyzed allylation of propargylic and allylic alcohols by allylsilanes: a facile synthesis of 1,5-enynes

Propargylic alcohols undergo smooth deoxygenative allylation with allylsilanes in the presence of a solution of 10 mol % of copper(II) tetrafluoroborate in acetonitrile to afford the corresponding 1,5-enynes in good to high yields under mild and neutral conditions. Scandium triflate is also found to catalyze efficiently the nucleophilic substitution of propargylic alcohols with allylsilanes.     

One-pot synthesis of aromatic homoallylic alcohols from aldehydes and Grignard reagents promoted by Titanium(IV) tetraisopropanolate

An efficient method of Titanium(IV) mediated one-pot reaction approaching aromatic homoallylic alcohols from aldehydes and dual Grignard reagents was developed with good isolated yields. This method could use aromatic-, heteroaromatic-, or aliphatic-aldehydes as starting materials. However, electron-riched benzaldehyde or cinnamaldehyde tended to precede further hydroxyl eliminations to give all conjugated structures as demonstrated.     

Highly selective, recyclable epoxidation of allylic alcohols with hydrogen peroxide in water catalyzed by dinuclear peroxotungstate

The highly chemo-, regio-, and diastereoselective and stereospecific epoxidation of various allylic alcohols with only one equivalent of hydrogen peroxide in water can be efficiently catalyzed by the dinuclear peroxotungstate, K2[[W(=O)(O2)2(H2O)]2(mu-O)].2H2O (I). The catalyst is easily recycled while maintaining its catalytic performance. The catalytic reaction mechanism including the exchange of the water ligand to form the tungsten-alcoholate species followed by the insertion of oxygen to the carbon-carbon double bond, and the regeneration of the dinuclear peroxotungstate with hydrogen peroxide is proposed. The reaction rate shows first-order dependence on the concentrations of allylic alcohol and dinuclear peroxotungstate and zero-order dependence on the concentration of hydrogen peroxide. These results, the kinetic data, the comparison of the catalytic rates with those for the stoichiometric reactions, and kinetic isotope effects indicate that the oxygen transfer from a dinuclear peroxotungstate to the double bond is the rate-limiting step for terminal allylic alcohols such as 2-propen-1-ol (1a).     

Iron-catalyzed boration of allylic alcohols with H3BO3 as an additive

A method for the synthesis of allylboronates by iron-catalyzed boration of allylic alcohols with H₃BO₃ as an additive is developed. The introduction of H₃BO₃ promotes the cleavage of C?O bond in allylic alcohols obviously. Functional groups, such as fluoro, chloro, bromo, alkyl, and alkoxy, are tolerated well. Thus, various allylboronates are obtained in acceptable yield.     

Chemoselective reduction of β-butyltellanyl α,β-unsaturated carbonyl compounds to allylic alcohols

(Z)-β-Butyltellanyl α,β-unsaturated carbonyl compounds were stereoselectively produced by hydrotelluration of alkynones or by an addition/elimination sequence from enol tosylates. The β-butyltellanyl-enones were chemoselectively reduced with NaBH₄/MeOH, NaBH₄·CeCl₃·7H₂O/MeOH and DIBAL-H systems to the corresponding allylic alcohols with retention of the Z stereochemistry.     

Ruthenium-catalyzed synthesis of allylic alcohols: boronic acid as a hydroxide source

Secondary allylic alcohols were synthesized from linear allylic halides or carbonates using a catalytic amount of a ruthenium complex in the presence of boronic acid. The effects of solvent, base, ruthenium precursor, and boronic acid were fully explored, and the scope of the reaction was extended to various substrates. We also describe a preliminary investigation towards an enantioselective process.     

One-pot synthesis and resolution of chiral allylic alcohols

Substituted α,β-unsaturated ketones were selectively reduced to the corresponding allylic alcohols under mild reaction conditions. The allylic alcohols thus obtained were kinetically resolved by lipase catalyzed transesterification in the same pot to afford chiral allylic alcohols in excellent enantioselectivity. Various lipases were screened for this one-pot transesterification of allylic alcohols. Effects of different solvent have also been studied under these conditions. Pseudomonas cepacia lipase immobilized on ceramic particles (PS-C) and on diatomaceous earth (PS-D) catalyzes this transesterification in diisopropyl ether in a highly efficient manner.     

Grignard additions to 2-uloses: synthesis of stereochemically pure tertiary alcohols

The addition of Grignard reagents to a number of 2-uloses has been investigated. Despite initial low diastereoselectivities it was found that tuning the ketone starting materials and studying solvent effects allowed formation of a single alcohol product.     

Stereoselective and diversity-oriented synthesis of trisubstituted allylic alcohols and amines

Stereoselective and diversity-oriented synthesis of trisubstituted olefins was achieved by using ortho-diphenylphosphanyl benzoate (o-DPPB) as a directing group for allylic substitution. The starting point of this methodology was a set of α-methylene aldehydes derived from Baylis-Hillman adducts. Subsequent addition of different organometallic reagents led to a variety of allylic alcohol substrates. After introduction of the reagent-directing o-DPPB group, copper-mediated allylic substitution with a wide range of Grignard reagents enabled the stereoselective construction of a large number of E-configured trisubstituted allylic alcohols and amines in excellent yields and stereoselectivities. Remarkable is the synthetic flexibility, which allows a wide range of permutations starting from an aldehyde followed by successive introduction of the substituents R(2) and R(3) from organometallic Grignard based reagents. Thus, starting from only a few precursors, a diversity-oriented synthesis of stereodefined trisubstituted allylic alcohols and amines becomes possible.     

醋酸烯丙酯选择性地合成烯丙基硒醚

醋酸烯丙酯被Pd(PPh3)4-SmI2还原，并发生中间体π-烯丙基钯络合物的极性 反转，而后与芳基硒溴化物作用，生成烯丙基硒醚．