The Effect of Substitution on the Solvolysis Rates of Benzhydryl Chlorides<sup>1</sup>
作者:Siegfried Altscher、Richard Baltzly、Samuel W. Blackman
DOI:10.1021/ja01134a054
日期:1952.7
Propargylic and Allenic Carbocycle Synthesis through Palladium-Catalyzed Dearomatization Reaction
作者:Bo Peng、Xiujuan Feng、Xin Zhang、Sheng Zhang、Ming Bao
DOI:10.1021/jo100211d
日期:2010.4.16
The dearomatization reaction of benzylic chlorides (1a-k), chloromethylnaphthalenes (1l-r), and naphthalene allyl chlorides (3a-d) with allenyltributyltin proceeded smoothly in the presence of Pd(PPh(3))(4) catalyst at room temperature to give the corresponding propargylated and/or allenylated dearomatization products (5, 5'; 6, 6'; and 7, respectively) in high to fair yields. The reaction of 1a-k proceeded smoothly in the presence of TBAF, whereas it was not necessary to use TBAF as an additive in the reactions of 1l-k and 3a-d. These reactions provided a new and efficient method for the synthesis of propargylic and allenic carbocycles.
Regioselective control using a catalyst switch in the reaction of diarylmethyl chlorides with allyltributylstannane
作者:Bo Peng、Xiujuan Feng、Xin Zhang、Liyun Ji、Ming Bao
DOI:10.1016/j.tet.2010.06.019
日期:2010.8
is described. The reaction pathway (allylativedearomatization vs cross-coupling) can be easily controlled using different catalysts. When reactions are performed in the presence of Pd2(dba)3 and PPh3, allylativedearomatization proceeds to provide satisfactory yield of the desired products. However, when Cy3P·HBF4 is employed as a catalyst instead of palladium, a Stille-type cross-coupling reaction
Lewis Acid‐Catalyzed Diastereoselective C−C Bond Insertion of Diazo Esters into Secondary Benzylic Halides for the Synthesis of α,β‐Diaryl‐β‐haloesters
作者:Fei Wang、Yoshihiro Nishimoto、Makoto Yasuda
DOI:10.1002/anie.202204462
日期:2022.7.18
Lewis acid-catalyzed carbon–carbon bond insertion of α-diazo esters into secondary benzylic halides is reported. Herein, the carbon chain elongation of acyclic benzylic halides and ring expansion in cyclic versions were realized to afford α,β-diaryl-β-halo carbonyl compounds with excellent diastereoselectivity. Computational study charted a specific mechanism involving the Lewis acid-promoted cleavage/re-formation