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[交流] Aldehydes and Ketones

Aldehydes and Ketones
The ability of the carbonyl group C=O to combine not only with a large variety of carbon frameworks but also with heteroatoms and heteroatom groups results in the proliferation of carbonyl compounds throughout the organic chemical world. The carbonyl group is present in many substances of biological and commercial importance, and carbonyl compounds provide the essential ingredients for a large number of organic syntheses. The chemistry of carbonyl compounds, occupies a central place in the study of organic chemistry.
醛或酮
由于羰基不仅和大量各种各样的碳框架结合，而且可以和杂原子、杂原子基团结合，因此导致了整个有机化学领域中羰基化合物的增殖。羰基存在于很多生物和商业的重要物质中，并且羰基化合物给大量的有机合成提供了重要的原料。因此，羰基化合物的化学作用在有机化学研究中占据一席之地。
Carbonyl compounds, represented by the general structure 1 are conveniently classified on the basis of groups that are attached to the carbonyl function. The attached groups are classified as follows:
(1) Type A groups: Hydrogen or organic frameworks in which the carbon attached to the
C = 0 is sp3-hybridized. This includes H—and alkyl groups, such as CH3—, CH3CH2—, (CH3)3C—, and substituted alkyl groups, such as C6H5CH2—, C13C—, HOCH2CH2—, etc.
(2) Type B and B‘ groups: Organic frameworks to which the carbon attached to the C = 0 is sp2-or sp-hybridized. If the attached group is C = C—or C^C—, it is designated as a type B group; if it is an aryl ring it is classed as a type B' group.
(3) Type C groups: Groups other than carbon or hydrogen. This include halogen,—OH,—NH2, etc.
（1) A型基团：氢或碳框架其中连接在C=O的C是sp3杂化的。这包括H—和烷基基团，如CH3—, CH3CH2—, (CH3)3C—和可取代的烷基基团，如C6H5CH2—, C13C—, HOCH2CH2—,等等。
（2）B和B’型基团：碳框架中连接C=O的C是sp2-或sp-杂化的。如果连接基团是C = C或 C^C，它被指定为B型基团。如果它是一个芳香环，它被归到了B基团类型。
（3）C型基团：除了碳或氢以外的其他基团，它包括了卤素—OH,—NH2, 等等。
Various combination of the attached groups G and G' lead to all the known types of carbonyl compounds. The present article is concerned only with those compounds in which the G groups are hydrogen (type A group), alkyl functions (type A group), and alkenyl, alkynyl, or aryl function (type B and B' groups), these combinations representing aldehydes and ketones (i.e., type AA, AB, and BB' ketones).
连接G and G'基团的不同组合导致所有已知羟基化合物类型。本文关注的只是那些G基团是H（A型基团），具有烷基官能团（A型基团），和烯基、炔基或芳基官能团（B 和 B'型基团的化合物，这些组合表示醛和酮（AA, AB, and BB'型基团）。
As a result of polarization of the carbonyl group . aldehydes and ketones have a marked tendency to add nucleophilic species (Lewis base) to the carbonyl carbon, followed by the addition of an electrophilic species (Lewis acids) to carbonyl oxygen: the reactions are classed as 1,2-nucleophilic addition.
作为羰基极化的结果，醛和酮有向羰基的碳上加亲核加成（路易斯碱）然后在羰基的氧上亲电加成（路易斯酸）的明显趋势，这种反应被叫做1，2亲核加成。
The position of the overall equilibrium is dependent on the nucleophilic: the stronger is the nucleophile, the farther the reaction proceeds to completion. Thus, certain carbon nucleophiles add so efficiently that for all practical purposes, the reactions are irreversible, whereas halogen nucleophiles add so inefficiently that, for all practical purpose, the reactions don't proceed at all.
整体平衡位置取决于亲核试剂：亲核试剂越强，反应进行的越完全。因此，某些碳亲核试剂的加成效率非常高，以致反应实际上是不可逆的，而卤素亲核试剂的加成效率却很低，实际上反应完全不能进行。

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