Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid （SA） to afford the corresponding α,β-unsaturated aldol products under solvent-free conditions...Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid （SA） to afford the corresponding α,β-unsaturated aldol products under solvent-free conditions in good to high yields at 45-80 ℃.展开更多
We developed a modified protocol for the oxidation of 2,3-allenyl alcohols using CuCI with l ： 1 combination of phenanthroline and bipyridine as the catalyst. To further investigate the applicability of this system, ...We developed a modified protocol for the oxidation of 2,3-allenyl alcohols using CuCI with l ： 1 combination of phenanthroline and bipyridine as the catalyst. To further investigate the applicability of this system, other types of alcohols such as allylic and propargylic alcohols have been tested： we found that both allylic and propargylic alcohols may be oxidized to the corresponding aldehydes or ketones using molecular oxygen in air as the oxidant with moderate to excellent yields.展开更多
A series of 2,3-dihydroquinazolin-4（1H）-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditi...A series of 2,3-dihydroquinazolin-4（1H）-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditions.The reaction was efficiently promoted by 10 mol%sulfamic acid（SA,H_2NSO_3H） and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity.展开更多
以磷石膏(PG)为催化剂催化合成缩醛(酮)。考察了醇酮摩尔比、催化剂用量、反应时间、带水剂种类及用量、催化剂重复使用次数等因素对合成环己酮乙二醇缩酮的影响,研究了PG催化合成12种缩醛(酮)的催化活性。实验结果表明,在PG用量为环己...以磷石膏(PG)为催化剂催化合成缩醛(酮)。考察了醇酮摩尔比、催化剂用量、反应时间、带水剂种类及用量、催化剂重复使用次数等因素对合成环己酮乙二醇缩酮的影响,研究了PG催化合成12种缩醛(酮)的催化活性。实验结果表明,在PG用量为环己酮的7.5%(w)、醇酮摩尔比为1.5、环己烷16 m L、反应时间2.5 h的条件下,PG催化合成环己酮乙二醇缩酮的产率可达99.9%以上;PG重复使用8次后,环己酮乙二醇缩酮产率仍达98.5%以上;在12种缩醛(酮)的制备反应中PG均表现出优良的催化性能,PG具有环境友好型固体酸催化剂的潜质,有望实现磷酸工业副产的回收利用和资源化处理。展开更多
Aldol reaction between simple benzaldehydes and ketones successfully happened in solvent- and catalyst-free condition. The desired products were obtained in moderate yield at suitable temperature. Heat was assumed as ...Aldol reaction between simple benzaldehydes and ketones successfully happened in solvent- and catalyst-free condition. The desired products were obtained in moderate yield at suitable temperature. Heat was assumed as the driving force for the reaction. This approach has obvious advantages to fully meet the requirement of the principles of green chemistry.展开更多
采用高效液相色谱方法(HPLC)对甲醇车的醛酮类污染物进行了定量定性研究.结果发现,瞬态时,安装三元转化器后燃烧汽油和甲醇车辆的总醛酮排放量转化效率分别为22.53%和48.95%.燃烧甲醇时,排放的主要是甲醛、乙醛和丙烯醛+丙酮,占总排放的...采用高效液相色谱方法(HPLC)对甲醇车的醛酮类污染物进行了定量定性研究.结果发现,瞬态时,安装三元转化器后燃烧汽油和甲醇车辆的总醛酮排放量转化效率分别为22.53%和48.95%.燃烧甲醇时,排放的主要是甲醛、乙醛和丙烯醛+丙酮,占总排放的97.18%,占燃烧汽油时排放的39.07%.未装三元催化器时,甲醇车的醛酮排放量高于汽油车,有三元催化器时甲醇车的醛酮排放量低于汽油车排放.稳态工况时,安装和未装三元催化器的甲醇车,在60 km/h工况下醛酮类污染物排放量最高,甲醛的平均转化效率最高,为88.50%.无论装载三元催化器与否,甲醇车的甲醛排放量均高于同工况的汽油车,在60、90和120 km/h 3个工况下,甲醇车的甲醛排放量分别比汽油车高332.94%3、74.47%和357.58%.展开更多
发展了一种由锰介导的简易高效的Reformatsky催化体系.在便宜易得锰粉的介导下,实现了镍催化剂高效催化碘代乙酸乙酯与醛酮的Reformatsky反应.以乙腈为反应溶剂,温和条件下可获得高收率的Reformatsky加成产物(up to 98%).此外,该催化方...发展了一种由锰介导的简易高效的Reformatsky催化体系.在便宜易得锰粉的介导下,实现了镍催化剂高效催化碘代乙酸乙酯与醛酮的Reformatsky反应.以乙腈为反应溶剂,温和条件下可获得高收率的Reformatsky加成产物(up to 98%).此外,该催化方法学还可放大至克级规模.展开更多
文摘Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid （SA） to afford the corresponding α,β-unsaturated aldol products under solvent-free conditions in good to high yields at 45-80 ℃.
文摘We developed a modified protocol for the oxidation of 2,3-allenyl alcohols using CuCI with l ： 1 combination of phenanthroline and bipyridine as the catalyst. To further investigate the applicability of this system, other types of alcohols such as allylic and propargylic alcohols have been tested： we found that both allylic and propargylic alcohols may be oxidized to the corresponding aldehydes or ketones using molecular oxygen in air as the oxidant with moderate to excellent yields.
文摘A series of 2,3-dihydroquinazolin-4（1H）-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditions.The reaction was efficiently promoted by 10 mol%sulfamic acid（SA,H_2NSO_3H） and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity.
文摘以磷石膏(PG)为催化剂催化合成缩醛(酮)。考察了醇酮摩尔比、催化剂用量、反应时间、带水剂种类及用量、催化剂重复使用次数等因素对合成环己酮乙二醇缩酮的影响,研究了PG催化合成12种缩醛(酮)的催化活性。实验结果表明,在PG用量为环己酮的7.5%(w)、醇酮摩尔比为1.5、环己烷16 m L、反应时间2.5 h的条件下,PG催化合成环己酮乙二醇缩酮的产率可达99.9%以上;PG重复使用8次后,环己酮乙二醇缩酮产率仍达98.5%以上;在12种缩醛(酮)的制备反应中PG均表现出优良的催化性能,PG具有环境友好型固体酸催化剂的潜质,有望实现磷酸工业副产的回收利用和资源化处理。
基金Project supported by the Chinese Academy of Sciences （Hundreds of Talents Program） and the National Natural Science Foundation fo China （No. 20972179）.
文摘Aldol reaction between simple benzaldehydes and ketones successfully happened in solvent- and catalyst-free condition. The desired products were obtained in moderate yield at suitable temperature. Heat was assumed as the driving force for the reaction. This approach has obvious advantages to fully meet the requirement of the principles of green chemistry.
文摘采用高效液相色谱方法(HPLC)对甲醇车的醛酮类污染物进行了定量定性研究.结果发现,瞬态时,安装三元转化器后燃烧汽油和甲醇车辆的总醛酮排放量转化效率分别为22.53%和48.95%.燃烧甲醇时,排放的主要是甲醛、乙醛和丙烯醛+丙酮,占总排放的97.18%,占燃烧汽油时排放的39.07%.未装三元催化器时,甲醇车的醛酮排放量高于汽油车,有三元催化器时甲醇车的醛酮排放量低于汽油车排放.稳态工况时,安装和未装三元催化器的甲醇车,在60 km/h工况下醛酮类污染物排放量最高,甲醛的平均转化效率最高,为88.50%.无论装载三元催化器与否,甲醇车的甲醛排放量均高于同工况的汽油车,在60、90和120 km/h 3个工况下,甲醇车的甲醛排放量分别比汽油车高332.94%3、74.47%和357.58%.
