FLUORODESULFURIZATION - NEW REACTION FOR FORMATION OF CARBON-FLUORINE BONDS
FLUORODESULFURIZATION - NEW REACTION FOR FORMATION OF CARBON-FLUORINE BONDS
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DOI：
10.1021/jo00881a007
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发表时间：
1976-01-01
影响因子：
3.6
通讯作者：
PERKINS, LM
中科院分区：
文献类型：
--
作者：
KOLLONITSCH, J;MARBURG, S;PERKINS, LM
本文描述了2-氨基硫醇和硫醇氨基酸在液态HF溶液中与氟代三氟甲烷、氯、N-氯代丁二酰亚胺或F-He混合物的反应。观察到C-S的裂解伴随着C-F键的形成，从而合成了氨基烷基氟化物和含氟氨基酸。D-青霉胺以接近定量的产率转化为3-氟-D-缬氨酸，而其他氨基硫醇则通过更复杂的途径提供了较低的产率。所提出的机制涉及S的高度氧化形式，如二盐基硫酸盐或三氟硫化物。这些非常正电的S部分应该是非常好的离开基团，与HF反应，要么像青霉胺那样在单分子意义上反应，要么可能像半胱氨酸那样通过双分子模式反应。在任何一种情况下，溶剂似乎是C-F键中F的来源。描述了一些醇的碳阳离子转化为硫醇的反应，这种转化可以通过适当的醇与硫化氢在液态氢氟酸中反应来影响。
The reactions of 2-aminothiols and thiol amino acids in liquid HF solution with either fluoroxytrifluoromethane, chlorine, N-chlorosuccinimide, or a F-He mixture are described. The cleavage of the C-S with concomitant formation of a C-F bond is observed, affording the synthesis of aminoalkyl fluorides and fluoro amino acids. D-Penicillamine was converted to 3-fluoro-D-valine in near-quantitative yield while other amino thiols, following more complex pathways, furnish lower yields of the respective fluoro products. The proposed mechanisms involve highly oxidized forms of S such as dihalosulfonium salts or trifluorosulfur dications. These very electropositive S moieties should be very good leaving groups, reacting with HF, either in a unimolecular sense as in the case of penicillamine, or possibly via a bimolecular mode, as in the case of cysteine. In either case, the solvent appears to be the source of F in the C-F bond. A carbocation-type conversion of some alcohols to thiols, which can be affected by reacting the appropriate alcohols with hydrogen sulfide in liquid HF, is described.