Stereoselective Synthesis of Versatile Intermediates for Clerodanes Total synthesis

The stereoselective synthesis of compounds 2a-d, attractive intermediates for the synthesis of clerodane diterpenes is described in 6 to 9 steps in good overall yields from commercially available racemic Wieland-Miescher ketone.     

烯丙基转移反应合成直链高烯丙基醇

研究了不同脂肪族和芳香族醛与6-甲基-6-苯基-7-烯-1,5-辛二醇的烯丙基转移反应, 同时考察了溶剂对反应的影响. 结果发现, 在In(OTf)3催化下, 以甲苯为溶剂, 由脂肪族醛合成的直链高烯丙基醇较芳香族醛具有较高的产率和较好的选择性, 所得产物结构经1H NMR, 13C NMR, IR, HRMS表征.     

Stereoselective Synthesis of δ-Selanyl Allylic Alcohols by Hydrozirconation of Propargyl Selenides

Hydrozirconation of propargyl selenides afford(E)-3-selanyl vinylzirconocenes chlorides 2.Intermediates 2 reacted with aldehydes to obtain δ-selanyl allylic alcohols.     

Heterocycle Synthesis Based on Allylic Alcohol Transposition Using Traceless Trapping Groups

Allylic alcohols undergo transposition reactions in the presence of Re₂O₇ whereby the equilibrium can be dictated by trapping one isomer with a pendent electrophile. Additional ionization can occur when the trapping group is an aldehyde or ketone, thus leading to cyclic oxocarbenium ion formation. Terminating the process through bimolecular nucleophilic addition into the intermediate provides a versatile method for the synthesis of diverse oxygen‐containing heterocycles. Understanding the relative rates of the steps in the sequence leads to the design of reactions which create multiple stereocenters with good to excellent levels of control.     

Stereoselective Synthesis of Tertiary Allylic Amines by Titanium-Catalyzed Hydroaminoalkylation of Alkynes with Tertiary Amines

Intermolecular hydroaminoalkylation reactions of symmetrical and unsymmetrical alkynes with tertiary amines take place in the presence of catalytic amounts of TiBn₄, Ph₃C[B(C₆F₅)₄], and a sterically demanding aminopyridinato ligand precursor. The resulting products, synthetically and pharmaceutically useful tertiary β,γ-disubstituted allylic amines, are formed in convincing yields and with excellent stereoselectivity. Particularly promising for future applications is the fact that even the industrial side product trimethylamine can be used as a substrate.     

A Short Stereoselective Total Synthesis of Racemic Patchouli Alcohol. Preliminary communication

A stereoselective four-step synthesis of racemic patchouli alcohol starting from the known 2,6,6-trimethyl-2,4-cyclohexadien-1-one [1] and 3-methylpent-4-en-1-ol [2] is described.     

Preparation of Protected Allylic Primary Amines from Allylic Phenyl Selenides

The reaction of an allylic selenide with an excess of an O-alkyl-N-chloro-N-sodiocarbamate in methanol affords an alkoxycarbonyl-protected allylic primary amine with allylic transposition. The preparation of several tert-butoxycarbonyl- and benzyloxycarbonyl-protected amines is described.     

Stereoselective Synthesis of Allylic Amines by One-Pot Tandem Reaction of Acetylenic Sulfone,Grignard Reagent,and N-Tosylimine

Polysubstituted allylic amines were regio- and stereoselectively synthesized by a one-pot tandem reaction of Cu(I)-catalyzed carbomagnesiation of acetylenic sulfones and its further reaction with N-tosylimine.     

Indium‐promoted Conversion of Allylic Bromide to Alcohol Moiety and Synthesis of Pipermethystine Skeletons

Dihydropyridone bromide ( 2 ) was converted to the corresponding alcohol ( 1 ) by reaction with indium in air or with indium followed by treatment with a sulfonyloxaziridine. The alcohol ( 1 ) was transformed in four steps to a phenylsulfone‐substituted pipermethystine derivative ( 10 ). Reductive cleavage of the phenylsulfone did not yield the pipermethystine natural product. Several new pyridone derivatives were synthesized.     

烯丙基金属有机化合物与不对称合成

本文综述了烯丙基金属有机化合物在不对称合成领域中的进展和应用,并讨论了有关亲核加成反应立体控制的反应机理等问题。     

Studies on the Synthesis of Morphinan Alkaloid： Preparation of the Key Allylic Silyl Ether Precursor

Morphinan alkaloid consisting of many diverse molecules has been attracting much attention of synthetic chemists because of their biologically significant activities and the intriguing structures1. As shown in the common nucleus 1 of these polycyclic frameworks, there is a unique quaternary carbon center with an aryl substituent representing a central synthetic challenge2. In connection with our constant investigations on the quaternary carbon chemistry3, we proposed a general and conceptually…     

Chemistry of Ethanediyl S,S-Acetals. VII. A Stereoselective Synthesis of Allylic Alcohols with cis-Configurated Double Bond

A new high yielding coupling reaction of C-2 monosubstituted 5,6-dihydro-1,4-dithiins with aldehydes is reported. In this way allylic alcohols having the cis-substituted double bond tied up by a sulfur-containing ring can be readily prepared. Subsequent stereoselective sulfur removal then affords allylic alcohols with cis-configurated double bond.     

手性烯丙基胺的合成进展

综述了近年来手性烯丙基胺的合成进展, 重点介绍了催化剂配体对化学选择性和对映选择性的影响, 并阐述了各种类型的反应机理.手性; 烯丙基胺; 催化