Titanium mediated alkylidenation of substituted cycloalkenones: scope and limitations
摘要:
The conversion of the cyclopent-2-enone 5 and cyclohex-2-enones 11a, c-e into corresponding alpha'-exo-alkylidene compounds using Ti(IV) catalysis, with PPh3 and an aldehyde, is described. (C) 2004 Elsevier Ltd. All rights reserved.
Regioselective palladium-catalyzed allylation of fulvenes
作者:Björn C. Söderberg、Lucinda R. Austin、Carol A. Davis、Jan-Erik Nyström、Jan O. V»gberg
DOI:10.1016/s0040-4020(01)80737-7
日期:1994.4
allylic acetates, and allylic carbonates in the presence of catalytic amounts of bis(dibenzylideneacetone)palladium(O) and triphenyl phosphine in good to excellent yield. A high degree of regioselectivity is observed with regard to the allylic substrate, and the most hindered position was predominately substituted. Inversion of stereochemistry of the allylic carbon by migration of the anion from the metal
General Enantioselective C−H Activation with Efficiently Tunable Cyclopentadienyl Ligands
作者:Zhi-Jun Jia、Christian Merten、Rajesh Gontla、Constantin G. Daniliuc、Andrey P. Antonchick、Herbert Waldmann
DOI:10.1002/anie.201611981
日期:2017.2.20
applicable chiral Cp ligand collection (JasCp ligands) with highly variable and adjustable structures. Their modular nature and their amenability to rapid structure variation enabled the efficientdiscovery of ligands for three enantioselective RhIII‐catalyzed C−H activation reactions, including one unprecedented transformation. This novel approach should enable the discovery of efficientchiral Cp ligands
The invention generally relates to novel polymers (SMAMPs) and their syntheses and use. The polymers exhibit promising properties of AMPs. In particularly, for example, a ring-opening metathesis polymerization (ROMP) platform was developed that allows syntheses of SMAMPs that employ a minimum number of norbornene-based building blocks and/or enable easy and independent variation of hydrophobic and hydrophilic groups in the monomer units and/or along the polymeric backbone to finetune and select desirable properties of the polymers.
Broad Scope [4 + 2] Cycloaddition of <i>o</i>-Carboryne with Pentafulvenes Using 1-Li-2-OTf-<i>o</i>-C<sub>2</sub>B<sub>10</sub>H<sub>10</sub> as Precursor
作者:Jie Zhang、Zaozao Qiu、Zuowei Xie
DOI:10.1021/acs.organomet.7b00574
日期:2017.10.9
from 1-Li-2-OTf-o-C2B10H10 undergoes an efficient [4 + 2] cycloaddition with pentafulvenes at room temperature to give a series of carboranonorbornenes in good to high isolated yields. This reaction is compatible with many functional groups and has a very broad substrate scope from 6-mono- to 6,6′-disubstituted pentafulvenes and from alkyl to aryl substituents. Further transformations of the resultant
从1-Li-2-OTf- o -C 2 B 10 H 10原位生成的邻-碳硼烷(1,2-脱氢-邻-甲硼烷)在室温下进行有效的[4 + 2]环戊五烯加成反应,得到一系列高或高分离产率的碳硼烷降冰片烯。该反应与许多官能团相容,并且具有非常宽的底物范围,从6-单-至6,6'-二取代的五氟戊烯和从烷基至芳基取代基。已经对所得的[4 + 2]环加成产物进行了进一步的转化,从而提供了各种多功能的邻氨基甲酸酯。
1,2-Dihydropentalenes from Fulvenes by [6 + 2] Cycloadditions with 1-Isopropenylpyrrolidine
In situ generated acetone pyrrolidine enamine undergoes [6 + 2] cycloadditions with fulvenes to give 1,2-dihydropentalenes. This ring annulation method works particularly well with 6-monosubstituted fulvenes and is subject to steric hindrance at C-6 of the fulvene. On the basis of mechanistic studies, optimal conditions have been developed for a one-pot synthesis of 1,2-dihydropentalenes using catalytic