New Successive Reactions Utilizing Functional Carbanions

烯醇酸酯是烯酮阴离子的等价物，因此在第一次反应后，烯醇酸酯转化为活性物质。利用这一性质，开发了新的连续反应和合成酯化物的新方法。提出了一种实用的合成油酸酯的方法：萘催化二溴酯先导油酸酯的还原岩性反应。通过串联[2+2]环加成-开环反应合成高z选择性烯烃：醇酯与酰基硅烷反应生成具有完美z选择性的聚取代乙烯基硅烷。这些乙烯基硅烷可以转化为四取代烯烃。烯酸酯与α-氧酮反应生成具有高z选择性的四取代烯烃。这些产物通过酸处理很容易转化为丁烯内酯。这两步的转化过程可以在一个锅中进行。通过串联[2+2]环加成- Michael反应高效合成碳环：由烯醇酸酯与酮类反应制备的β-内酯烯醇酯具有高亲核性。通过串联[2+2]环加成-迈克尔加成，酯化物与在适当位置上具有不饱和食层单元的酮类反应。产物易转化为多取代环烯烃，收率高。通过这种串联反应，可以构造五元、六元和七元碳环。由于串联反应的产物是酯烯醇酯，因此它们具有亲水性。利用这种性质，级联反应可以得到复杂的分子。采用串联法合成了新型三醌倍半萜类化合物黄瓜素E。

Ynolates are ketene anion equivalens, so that ynolates are converied into reactive species after the first reaction. Using this property, novel successive reactions as well as new synthetic method of ynolates have been developed1. Practical synthetic method of ynolates: Naphithalene catalyzed reductive lithation of dibromo esters leading ynolates was developed.2. Highly Z-selective synthesis of alkenes via tandem [2+2] cycloaddition - ring-opening reaction: Ynolates reacted with acylsilanes to afford polysubstituted vinyl silanes with perfect Z-selectivity. These vinyl silanes produced can be converted into tetrasubstituted alkenes. Ynolates reacted with α-oxyketones to give tetrasubsituted alkenes with high Z-selectivity. These prodeucts were easily converted into butenolides by treatment of acids. This 2-step conversion prosess can be carried out in one-pot.3. Efficient syntheses of carbocycles via tandem [2+2] cycloaddition - Michael reaction: β-Lactone enolates prepared by reaction of ynolates with ketones have high nucleophiliciy. The reaction of ynolates with ketones having an unsaturated eater unit in a proper positionprovided bicyclic β-lactones via tandem [2+2] cycloaddition - Michael addition. The products were easily converted to polysubstituted cycloalkenes in good yield. By this tandem reaction, five-, six- and seven-membered carbocycles can be constructed. Since the products of the tandem reaction are ester enolates, they have uncleophilicity. Taking advantage of this properties, cascade reactions can be carried out to give complex molecules.4. Total synthesis of cucumin E, novel type of triquinane sesquiterpenoid, was achieved using the tandem reaction.