英语翻译

英语翻译
A 500-mL,three-necked,round-bottomed flask is equipped with a 25-mL pressure-equalizing dropping funnel,a mechanical stirrer,and a Claisen adapter fitted with a nitrogen inlet adapter and a low-temperature thermometer (Note 1).The flask is charged with 115 g (0.077 mol) of (R)-(−)-carvone (Note 2),10.8 g (0.079 mol) of 1-methyl-1-(trimethylsilyl)allene (Note 3),and 180 mL of dry dichloromethane (Note 4),and then cooled below −75°C with a dry ice–acetone bath while a solution of 17.4 g (0.092 mol) of titanium tetrachloride (Note 5) in 10 mL of dichloromethane is added dropwise over 1 hr.After 30 min,the cold bath is removed,and the reaction mixture,which appears as a red suspension,is allowed to warm to 0°C over approximately 30 min.The resulting dark red solution is poured slowly into a 2-L Erlenmeyer flask containing a magnetically stirred mixture of 400 mL of diethyl ether and 400 mL of water (Note 6).The aqueous phase is separated and extracted with two 200-mL portions of ether.The combined organic phases are washed with 250 mL of water and 250 mL of saturated sodium chloride solution,dried over anhydrous magnesium sulfate,and concentrated at reduced pressure using a rotary evaporator.The residual yellow liquid is distilled through a 15-cm Vigreux column at reduced pressure to afford 17.5 g (82%) of the bicyclonoenone 1 as a very-pale-yellow liquid,bp 98–101°C (0.03 mm),[α]D20 −157.8 ± 0.8 (1.57,CH2Cl2) (Note 7) and (Note 8).