Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

• product 19c, the latter was obtained in a greatly reduced yield, perhaps due to less ring strain providing a thermodynamic driving force. In 2013, Mannathan et al. discussed a Ni-catalyzed intermolecular three-component difunctionalization of oxabicyclic alkenes 1 with organoboronic acids 20 and alkynes

• ) and O-benzoylhydroxylamine derivatives 54 (Scheme 9) [43]. While the scope of bicyclic alkenes was quite extensive with aza-, carbo-, and oxabicyclic alkenes being amenable to the reaction, electron-deficient substrates resulted in lowered yields. Of note, the reaction is highly regioselective with

• proceeds similarly to Nakamura’s Fe-catalyzed methodology (Scheme 13) [48]. In 2017, the Cheng laboratory investigated the Co-catalyzed ring-opening/dehydration of oxabicyclic alkenes via the C–H activation of arenes (Scheme 15) [50]. First, the group explored the ortho-naphthylation of N-pyrimidinylindole

Acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with alcohols

• Katrina Tait,
• Alysia Horvath,
• Nicolas Blanchard and
• William Tam

Beilstein J. Org. Chem. 2017, 13, 2888–2894, doi:10.3762/bjoc.13.281

• ; alcohol nucleophiles; cyclopropanation; heterobicyclic compounds; ring-opening reactions; Introduction Heterobicyclic alkenes are useful templates to generate complex cyclic and acyclic systems [1][2]. 3-Aza-2-oxabicyclic alkenes are particularly interesting due to their asymmetric nature and the ability

• to modify selected components of the molecule to create vastly different products. 3-Aza-2-oxabicyclic alkenes are generally modified in one of four ways (Scheme 1). One of the most interesting manipulations of 3-aza-2-oxabicyclic alkenes is the modification of the alkene component. The manipulation

• ], and cycloadditions using nitrile oxides to provide 15 and 16 [7]. In the literature, there are also many examples of the cleavage of the C–O bond of 3-aza-2-oxabicyclic alkenes 1 (Scheme 3). This includes the use of protic acid [8], using metal catalysts such as Pd [9], Fe or Cu [10], In [11

Gold-catalyzed reaction of oxabicyclic alkenes with electron-deficient terminal alkynes to produce acrylate derivatives

• Yin-wei Sun,
• Qin Xu and
• Min Shi

Beilstein J. Org. Chem. 2013, 9, 1969–1976, doi:10.3762/bjoc.9.233

• Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, People’s Republic of China 10.3762/bjoc.9.233 Abstract Oxabicyclic alkenes can react with electron-deficient terminal alkynes in the presence of a gold catalyst under mild conditions

• reactions is also discussed. Keywords: gold catalysis; oxabicyclic alkenes; substituted acrylates; Introduction Oxabicyclic alkenes are common intermediates in organic synthesis since these compounds can be easily prepared and have a high reactivity for further transformations [1][2][3][4][5][6][7][8

• these previous findings, we envisaged that oxabicyclic alkenes could also react with electron-deficient alkynes in the presence of gold catalysts to generate a new C–C or C–O bond thereby releasing the oxabicyclic alkenes of their ring strain. In this paper, we report the formation of (Z)-acrylate

Recent advances in transition-metal-catalyzed intermolecular carbomagnesiation and carbozincation

• Kei Murakami and
• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 278–302, doi:10.3762/bjoc.9.34

• cyclization reaction (Scheme 44). Under Nakamura’s iron-catalyzed carbometalation reaction conditions (shown in Scheme 17), the reaction of oxabicyclic alkenes provided ring-opened product 4m through a carbomagnesiation/elimination pathway (Scheme 45, reaction 4l to 4m) [82]. In contrast, the use of the 1,2

• . Zirconium-catalyzed alkylmagnesiation. Titanium-catalyzed carbomagnesiation. Three-component coupling reaction. Iron-catalyzed arylzincation reaction of oxabicyclic alkenes. Reaction of allenyl ketones with organomagnesium reagent. Regio- and stereoselective reaction of a 2,3-allenoate. Three-component

Iridium-catalyzed asymmetric ring-opening reactions of oxabicyclic alkenes with secondary amine nucleophiles

• Dingqiao Yang,
• Ping Hu,
• Yuhua Long,
• Yujuan Wu,
• Heping Zeng,
• Hui Wang and
• Xiongjun Zuo

Beilstein J. Org. Chem. 2009, 5, No. 53, doi:10.3762/bjoc.5.53

• ring-opening reactions of oxabicyclic alkenes with various aliphatic and aromatic secondary amines are reported for the first time. The reaction gave the corresponding trans-1,2-dihydronaphthalenol derivatives in good yields with moderate enantioselectivities in the presence of 2.5 mol % [Ir(COD)Cl]2

• and 5 mol % bisphosphine ligand (S)-p-Tol-BINAP. The trans-configuration of 3f was confirmed by X-ray crystallography. Keywords: chiral bisphosphine ligand; iridium catalyst; oxabicyclic alkenes; ring-opening reaction; Introduction Substituted dihydronaphthalenes are important molecules with

• metal catalysts may be used for asymmetric ring-opening reactions of oxabicyclic alkenes. These include complexes of copper [20][21][22][23][24][25], palladium [14][15][26][27][28][29][30][31], iron [32], and nickel [33][34][35][36]. Recently, we reported for the first time iridium-catalyzed asymmetric