The reaction of hexafluoropropene oxide with alkyl lithium reagents

A series of alkyl lithium reagents has been found to react with hexafluoropropene oxide in the presence of ether to give carbinols of the type CF₃CFRCR₂OH. Butyllithium in hexane reacts “abnormally” to give the carbinol CF₃C(OH) BuCF₂Bu. Mechanisms to account for these difference are presented.     

Self-condensation reaction of alkylbenzothiazoles with grignard reagents

2-alkylbenzothiazoles undergo Claisen-type self-condensation reaction simply on treatment with Grignard reagents.     

3-氰基吡啶与Grignard试剂的反应研究

3-取代酰基吡啶可由3-氰基吡啶与相应的卤代烷基镁加成,然后酸化水解来制备.我们曾用该法顺利地制备了一系列的3-取代酰基吡啶,另外还得到少量的4-烷基-3-取代酰基吡啶.但当用氯化苄基镁时,只得到少量的3-取代酰基吡啶,而主要产物却是4-苄基-3-氰基吡啶.为了探讨这两种反应中各组分的相对含量,用高压液相色谱分别对3-氰基吡啶与溴化丁基镁、氯化苄基镁的反应产物进行了分析.为了解释反应产物的异常现象,对反应物进行了量子化学计算,用前线轨道理论对以上反应进行了讨论.     

Functionalized ketones by iron mediated reaction of grignard reagents with acyl chlorides

The iron(III)-catalyzed cross-coupling reaction between Grignard reagents and acyl chlorides was found to be widely applicable to the synthesis of various functionalized ketones in good yields under mild conditions; the series of examples includes the synthesis of chiral methyl ketones and symmetric diketones.     

The reaction of grignard reagents with 1,3-dioxolanes. Influence of solvation; kinetics and mechanism

The reaction of 2-ethyl-1,3-dioxolane (D) with ethylmagnesium bromide, solvated by one equivalent of a basic solvent (E) (diethyl ether, diisopropyl ether and perdeutero-tetrahydrofuran) was studied in benzene at 40.5°. Ring-cleavage of the dioxolane occurs with first-order kinetics in two different coordination complexes, i.e. EtMgBr·E·D and EtMgBr·2D. When the Grignard reagent is in excess, an additional second-order reaction takes place between the complex EtMgBr·E·D and the monosolvated Grignard reagent. The rate constants are related to the basicities of the different ethers, E, used. The results confirm that the reaction proceeds via a transition state with oxocarbonium ion character. In agreement with this concept the reaction rates decrease with increasing basicity of the complexing ethers as the Lewis acidity of the attacking Grignard reagent is lowered.     

Preparation of ketones by direct reaction of grignard reagents with acid chlorides in tetrahydrofuran

Grignard reagents react with acid chlorides in tetrahydrofuran at low temperature to produce ketones in excellent yields. The results reported here strongly indicate the importance of the solvent in Grignard reagent chemistry.     

Electrophilic reaction of nitric oxide with Wittig reagents

Reaction of nitric oxide (NO) with p-substituted benzyl triphenylphosphonium chlorides or bromides (Wittig reagents) in CH₂Cl₂ under argon undergoes electrophilic attack of NO on the carbon center of phosphonium ylides, producing benzonitriles.     

Amination of grignard reagents with retention of configuration

[see reaction]. The stereochemistry of electrophilic amination has been probed using the chiral Grignard reagent 5, in which the magnesium-bearing carbon atom is the sole stereogenic center. Amination with azidomethyl phenyl sulfide 1 and with O-sulfonyloxime 2 were found to proceed with full retention of configuration.