碳环的

L-prolinamide/PPTS system was developed to catalyze Robinson annulation of 1,3-cyclohexanedione derivatives. Using this system, the functionalized carbon chain of Wieland-Wiescher ketone could be synthesized in high enantioselectivity, which was a useful synthon for structural diversity of total synthesis of natural product.

二、发现了L-prolinamide／PPTS体系可以催化Ronbinson环化1，3-环己二酮衍生物，实现含季碳且具有多官能团侧链的Wieland-Wiescher酮高对映选择性的合成，为天然产物结构多样性的合成奠定了基础。

The cis novel bisoxazoline ligands L1-L4 have been synthesized through the treatment of new cis dihydroxy diamide with p-toluenesulfonyl chloride in the presence of catalytic quantity of 4--pyridine, and the cis dihydroxy diamide could be achieved from the condensation of the amino alcohols and cis cyclopropane dicarbonyl chloride prepared via oxidation and halogenation from cis-2,2-dimethyl-3-formylcyclopropanecarboxylate with DCC.

我们以蒈醛酸内酯为起始原料，经过氧化反应、酰氯化反应得到顺式环丙烷二酰氯，然后在二环己基碳二亚胺的催化下与相应的氨基醇反应合成了顺式二羟基酰胺，再用对甲苯磺酰氯将羟基活化，最后在二甲氨基吡啶的催化下关环合成顺式双噁唑啉配体L1～L4。

Purine: Any of a class of heterocyclic compounds with a two-ring structure composed of carbon and nitrogen atoms.

嘌呤：嘌呤是对由碳、氮原子组成的双环结构的杂环化合物的统称。

Purine: Any of a class of heterocyclic compounds with a two-ring structure composed of carbon and nitrogen atom s.

嘌呤：嘌呤是对由碳、氮原子组成的双环结构的杂环化合物的统称。

Purine: Any of a class of heterocyclic compound s with a two-ring structure composed of carbon and nitrogen atoms.

嘌呤：嘌呤是对由碳、氮原子组成的双环结构的杂环化合物的统称。

Amino-2-methylpropanol was utilized as a chemical modifying reagent to modify carboxyl groups in unsaturated fatty acids into nitrogen-containing heterocycles, which effectively suppressed the migration of double bonds of the alkenyl within the electron impact source and led to regular informative mass spectra indicative of the position of the olefinic bonds in the chain.

以2-氨基－2-甲基丙醇为脂肪酸的化学修饰试剂，将不饱和脂肪酸羧基化学修饰试剂，将不饱合脂肪酸羧基化学修饰成含氮杂环，从而避免了链烯基中碳碳双键在EI源中的移动，并使质谱呈现显示双键位置的规范信息。

Aromatic rings can be joined at a pair of adjacent carbons to yield compounds such as naphthalene, anthracene and chrysene

芳环能在一对相邻碳上结合，生成萘、葸和？傅然油母质中的芳香烃结构含有被苯环共振键稳定的自由电子。

Dihydrojasmone was synthesized from2-hexyl-5-methyl-1,2-oxaborolane,prepared frommethyl vinyl ketone and hexene,via the homologationwith 〓 followed by PCC oxidation and intra-molecular condensation.In stead of the oxidation ofthe C-B bond of 1,2-oxaborolane,fluoride inducedhalogenation of 2-alkoxy-1,2-oxaborolane was found togive 3-halopropanol.

硼氢化甲基乙烯基酮和已烯得到的2-已基-5-甲基-1，2-氧硼杂环戊烷与〓反应，再经PCC氧化，分子内缩合得到二氢茉莉酮。1，2-氧硼杂环戊烷的C-B键除氧化断裂之外，也能够在〓或KF作用下卤化断裂成碳卤键。

In a DMF solution of CuCl〓-ethanolamine-acetic acid (1: 2: 2), 27 formed a highly oxidized heterocyclic compound 2-hydroxymethyl-naphtho [1, 2-a] oxazole (30) by the carbon-nitrogen coupling and carbon-oxygen coupling with the ligand of ethanolamine, which brings a chance to develop a novel approach to this heterocyclic compound via one-pot reaction of phenols under mild condition.

在氯化铜—乙醇胺—乙酸（1：2：2）的DMF溶液中，27与配体乙醇胺发生碳氮偶合与碳氧偶合，生成深度氧化的杂环化合物：2-羟甲基-萘并[1，2-a]〓唑（30）。这可望为酚类一锅化直接转化为30及其类似物提供一种简便的新合成路线。

Through the processes of grinding bastnaesite ore concentrate, mixing the ore powder with NaCO3 in the ratio of 1 to 0.1-0.4, roasting the mixture at 400-800 deg.c for 1-6 hr, elution of the roasted sand with hot water to obtain NaF, drying filtered drag after eluting NaF and mixing the dried drag with ammonium chloride, roasting the mixture at 300-600 deg.c for 1-3 hr, hot water soaking to obtain rare earth chloride solution, extraction with 20% kerosine solution of naphthenic acid, and hydrochloric acid counter extraction to obtain rare earth chloride product.

本发明涉及一种氯化铵法从氟碳铈精矿提取氯化稀土的方法，首先将氟碳铈原精矿磨细，并与NaCO 3 混合，其比例为原矿∶NaCO 3 ＝1∶0.1～0.4，混合均匀后在400℃～800℃焙烧1～6小时，焙砂用热水洗出NaF，洗出NaF的滤渣干燥后与氯化铵混合，于300℃～600℃焙烧1～3小时，再用热水浸取得到氯化稀土溶液，用20％的环烷酸煤油液萃取，再采用盐酸反萃得到氯化稀土产品。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。