Synthesis of bicyclic γ-butyrolactone derivatives by rhodium catalyzed intramolecular C–H insertion of α-dizao α-phosphoryl cycloalkyl esters

Synthesis of α-exo-Methylene-γ-butyrolactones: Recent Developments and Applications in Natural Product Synthesis

“…Bicyclic ring scaffolds were also prepared by employing a cyclic alcohol as the starting material (Scheme 9). 28b, 29 The -exo-methylene--butyrolactone 47 was formed in a 10:1 trans/cis ratio and insertion took place predominantly into the equatorial C-H bond, with spiro analogue 48 being obtained as a by-product. Finally, this methodology has also been used in the total synthesis of lignans and eudesmanolides (vide infra, Section 4).…”

“…Scheme 29 Tang's formal synthesis of (-)-xanthatin Anthecotulide (109) and hydroxyanthecotulide (110) are bioactive linear sesquiterpene lactones (Scheme 30). 61 These irregular structures demonstrated antibacterial, antimalarial, trypanocidal, and leishmanicidal activity.…”

Catalyst-free and solvent-free oxidation of cycloalkanes (C5-C8) with molecular oxygen: Determination of autoxidation temperature and product distribution

“…Glutaric acid, heptanedioic acid and octanedioic acid obtained from oxidation of the corresponding cycloalkane directly or indirectly are important precursors in the production of various macromolecule polymers too [20][21][22][23][24]. In addition, cycloalkanols and cycloalkanones are important intermediates and solvents in the chemical industry and academic research [25][26][27][28][29][30][31]. To realize this necessary transformation from cycloalkanes to their oxidized products, several oxidants can be employed, such as iodosylbenzene [32][33][34][35][36][37][38], iodosylbenzene diacetate [34,[38][39][40], tert-butyl hydroperoxide [41][42][43][44][45][46][47][48][49], m-chloroperoxybenzoic acid [50][51][52][53][54][55], hydrogen peroxide [56][57][58][59][60][61][62][63], mole...…”

α-Alkylidene-γ-butyrolactone Formation via Bi(OTf)3-Catalyzed, Dehydrative, Ring-Opening Cyclizations of Cyclopropyl Carbinols: Understanding Substituent Effects and Predicting E/Z Selectivity

“…Synthesis of the ABL framework is an ongoing endeavor for the synthetic community. As such, several extensive reviews have been published highlighting the diverse approaches that can be taken toward the scaffold. ,, The general synthetic approaches to the ABL core have been classified into the following types: alkylidenation of γ-butyrolactones, various lactonization approaches, tandem (or sequential) intramolecular C–H insertion/olefination, the Dreiding–Schmidt organometallic approach, cross-methathesis between α-methylene-γ-butyrolactones and olefins, intramolecular enyne metathesis reactions, Pd-catalyzed cross-couplings, Diels–Alder and retro-Diels–Alder reactions, radical cyclizations, and Baeyer–Villiger reactions on cyclobutanones . Despite the abundant literature, the diversity within the ABLs has made the pursuit of strategic ABL targets and the development of methodologies to access them persistently meaningful endeavors in the synthetic community …”