Process for the preparation of bulky alkyldiarylphosphines and
申请人:Union Carbide Corporation
公开号:US04668823A1
公开(公告)日:1987-05-26
A process for the selective production of bulky alkyldiarylphosphines and unsymmetrical dialkylarylphosphines comprising reacting a first Grignard reagent having a bulky alkyl group with an aryldichlorophosphine and thereafter and without isolating the resulting bulky alkylarylchlorophosphine intermediate, reacting said intermediate with a second Grignard reagent having a different, less bullky alkyl group or an aryl group to provide the product phosphine.
1′-cyclohexane-1,5-dione with Grignardreagents give the corresponding 1-hydroxy-5-ones and/or 1,5-dihydroxy derivatives, though there is a competing reduction of the carbonyl groups in the starting material by alkylmagnesium halides possessing β-hydrogen atoms. The dihydroxy derivatives with one or two hydrogen atoms introduced at positions 1 and/or 5 appeared to be highly unstable, undergoing spontaneous
螺[5]二茂铁酚-3,1'-环己烷-1,5-二酮与格利雅试剂的反应给出了相应的1-羟基-5-酮和/或1,5-二羟基衍生物,尽管存在竞争性还原。原料中的羰基是由具有β-氢原子的烷基卤化镁制成的。在位置1和/或5处引入一个或两个氢原子的二羟基衍生物看来是高度不稳定的,经历自发脱水成相应的醚。对获得的化合物的1 H和13 C NMR光谱进行详细分析,揭示了二茂铁碳杂环戊二烯桥的完全刚性。
Nickel-Catalyzed Ring-Opening C–O Functionalization of <i>peri</i>-Xanthenoxanthenes for 8-Substituted Binaphthol Synthesis
Herein, we disclose the Ni-catalyzed ring-opening C–O functionalization of peri-xanthenoxanthenes using Grignard reagents that forms 8-monofunctionalized binaphthols. 1,2-Bis(dicyclohexylphosphino)ethane was the best ligand for alkylations and ICy for arylation. After mechanistic investigations, we assumed that the reaction proceeds via C–O reduction and subsequent C–O functionalization. To verify
Nucleophilic reactions with Grignardreagents and the Mukaiyama aldol reactions of the naphthaldehydes having the (2,4, 6-triisopropylphenyl)sulfinyl group produced products with high stereoselectivity. In these reactions, the stereochemistry of the major products changes depending on the Lewis acids used. Reduction of the 2-acyl-1-[(2,4,6-triisopropylphenyl)sulfinyl]naphthalenes also proceeds with