Bridged ring compounds. VIII. 1-Halobicyclo[2.2.-2]octanes

Correlation of Gas-Phase Stability of Bridgehead Carbocations with Rates of Solvolysis and ab Initio Calculations

“…The FT ICR Spectrometer. The study was carried out on a modified Bruker CMS-47 FT ICR mass spectrometer used in previous studies. , A detailed description is given in refs and . Some modifications have been introduced with respect to the standard instrument.…”

Through-bond transmission of substituent effects in the bicyclo[2.2.2]octane ring system: solvolysis of 4-deuterio- and 4-metalloidal (M(CH3)3, M = silicon, germanium and tin)-substituted bicyclo[2.2.2]oct-1-yl p-nitrobenzenesulfonates and methanesulfonates

“…The combined extract was washed with saturated sodium bicarbonate solution and dried, and the solvent was removed to afford the crude 1-acetoxybicyclo-[2.2.2]octane as an orange oil, 18.0 g (97%). A sample was distilled to afford a colorless oil (bp 70 "C/0.6 mm), which solidified: mp [34][35][36] °C; NMR (CC14) 1.4-2.3 (16 H, m). A mixture of crude acetate (20.2 g, 0.12 mol), sodium methoxide (13.0 g, 0.24 mol), and absolute methanol (100 mL) was refluxed with stirring for 2 h. The resulting slurry was poured on to ice/water and extracted with ether.…”

“…4%). Fractional Kugelrohr distillation /sublimation followed by recrystallization from aqueous ethanol afforded 4-(trimethylstannyl)bicyclo[2.2.2]octan-l-ol as a white solid (4.5 g, 88%); mp 123-124 °C; *H NMR (360 MHz, CDC13) -0.16 (9 H, s), 1.05 (1 H, br s), 1.40-1.48 (6 H, m), 1.62-1.78 (6 H, m); 13C NMR (CDCI3), relative to Me4Si) 68.48 (Cl), 35.00 (C2), 31.51 (C3), 21.65 (C4),-12.43 (SnMe3). Anal.…”

“…(3 H, s, CH3S03) 2.09-2.00 (6 H, m, CH2CH2), 1.74-1.62 (6 H, m, CH2CH2), -0.02 (9 H, s, Me3Ge), 13C NMR (75 MHz, CC13) 92. 35 (Cl), 31.74 (C2), 28.95 (C3), 19.66 (C4), 40.86 (CH3S03), -5.69 (Me3Ge); X = SnMe3, mp 87-89 °C, NMR (360 MHz, CDC13) 2.93 (3 H, s, CH3S03) 2.09-2.00 (6 H, m, CH2CH2), 1.90-1.80 (6 H, m, CH2CH2), -0.06 (9 H, s, Me3Sn), 13C NMR (75 MHz, CDC13) 92.07 (Cl), 32.48 (C2), 31.62 (C3), 20.65 (C4), 40.91 (CH3S03), -12.45 (Me3Sn). Conductance Kinetics Procedure.…”

11-Step Total Synthesis of Pallambins C and D

“…When attempts at direct conversion of 10 to 12 failed, intermediate 10 was treated with AcBr to furnish 11 in 57% overall yield ( Scheme 1 ). 14 Although this cyclization effectively installed the C-ring of the pallambins, it necessitated a nonstrategic reduction to replace the alkyl bromide with hydrogen ( 11 → 12 , AIBN, SnBu 3 H, 90%). One-pot desaturation proceeded smoothly delivering enone 13 in 60% yield.…”