Cascade trifluoromethylthiolation and cyclization of N-[(3-aryl)propioloyl]indoles

• Ming-Xi Bi,
• Shuai Liu,
• Yangen Huang,
• Xiu-Hua Xu and
• Feng-Ling Qing

Beilstein J. Org. Chem. 2020, 16, 657–662, doi:10.3762/bjoc.16.62

• strategy in the synthesis of a series of CH2SCF3-substituted heterocycles. For the construction of SCF3-substituted cyclic compounds, normally proper alkynes are chosen as the substrates for cascade reactions [28][29][30][31][32]. In 2015, Wang developed an oxidative radical cyclization of aryl alkynoate

Cobalt- and rhodium-catalyzed carboxylation using carbon dioxide as the C1 source

• Tetsuaki Fujihara and
• Yasushi Tsuji

Beilstein J. Org. Chem. 2018, 14, 2435–2460, doi:10.3762/bjoc.14.221

• , respectively. The reaction of unsymmetrical 1-phenyl-1-hexyne with 18a afforded 19d-H and 19d-Et regioselectively. In addition, an alkyne with a thiophene ring regioselectively produced the desired product 19e-Me after methylation with MeI. It is noteworthy that an alkynoate was also converted into the

1H-Imidazol-4(5H)-ones and thiazol-4(5H)-ones as emerging pronucleophiles in asymmetric catalysis

• Antonia Mielgo and
• Claudio Palomo

Beilstein J. Org. Chem. 2016, 12, 918–936, doi:10.3762/bjoc.12.90

• ester moiety of the allenoate. Examination of different allenoates revealed that the dibenzosuberyl ester provided the best results. The scope of these catalysts was also proven in the reaction with alkyne substrates. For instance, both thiazol-4(5H)-one 82 and oxazol-4(5H)-one 85 react with alkynoate

• ’-silyloxyenone 29 [73]. Elaboration of the thiazolone Michael adducts [73]. Enantioselective γ-addition of oxazol-4(5H)-ones and thiazol-4(5H)-ones to allenoates promoted by C6/C7 [36]. Enantioselective γ-addition of thiazol-4(5H)-ones and oxazol-4(5H)-ones to alkynoate 83 promoted by C6/C7 [36]. Proposed

Copper-catalyzed stereoselective conjugate addition of alkylboranes to alkynoates

• Takamichi Wakamatsu,
• Kazunori Nagao,
• Hirohisa Ohmiya and
• Masaya Sawamura

Beilstein J. Org. Chem. 2015, 11, 2444–2450, doi:10.3762/bjoc.11.265

• . Keywords: alkylborane; alkynoate; conjugate addition; copper; multisubstituted alkene; Introduction Copper-mediated conjugate additions of organometallic reagents to alkynoates are powerful tools for the synthesis of multisubstituted alkenes [1][2][3][4][5][6][7][8]. Because of their broad availability

• methoxide to form trisubstituted alkenylstannanes [15]. The latter reaction pathway involved Sn-trapping of an alkenylcopper intermediate that was formed through syn-carbocupration of an alkylcopper(I) species across the C–C triple bond of the alkynoate. We envisioned that 1,2-hydroalkylation of the

• mode. The syn stereoselectivity was excellent regardless of the substrate structure, and a variety of functional groups were tolerated in both the alkylborane and the alkynoate. Results and Discussion Alkylborane 2a (0.275 mmol), which was obtained via hydroboration of styrene (1a) with the 9

Olefin cross metathesis based de novo synthesis of a partially protected L-amicetose and a fully protected L-cinerulose derivative

• Bernd Schmidt and
• Sylvia Hauke

Beilstein J. Org. Chem. 2014, 10, 1023–1031, doi:10.3762/bjoc.10.102

• perdeuteration of an alkynoate derived from L-threonine (giving a 2,2,3,3-tetradeuterated amicetose) [26], enantioselective hydroboration of hetero Diels–Alder adducts [27], stereoconservative diazotation of L-glutamic acid [28][29], diastereoselective addition of methylmagnesium bromide to enantiopure 2

Asymmetric total synthesis of smyrindiol employing an organocatalytic aldol key step

• Dieter Enders,
• Jeanne Fronert,
• Tom Bisschops and
• Florian Boeck

Beilstein J. Org. Chem. 2012, 8, 1112–1117, doi:10.3762/bjoc.8.123

• smoothly with iodide 18 and could be transformed into the aryl alkynoate 19 under mild acidic conditions, leaving the acetonide unscathed. The TBS group could now be cleaved by the addition of tetrabutylammonium fluoride in THF. When subjected to Lindlar catalyst and 1 atm of hydrogen, the resulting ethyl