Organofluorine chemistry: Difluoromethylene motifs spaced 1,3 to each other imparts facial polarity to a cyclohexane ring.
Organofluorine chemistry: Difluoromethylene motifs spaced 1,3 to each other imparts facial polarity to a cyclohexane ring.
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DOI：
10.3762/bjoc.12.281
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发表时间：
2016
影响因子：
2.7
通讯作者：
O'Hagan D
中科院分区：
文献类型：
--
作者：
Jones MJ;Callejo R;Slawin AM;Bühl M;O'Hagan D
2,2-二甲基-5-苯基-1,1,3,3-四氟环己烷已被制备并表征为包含1,3相关CF2基团的面极化环己烷的例子。环的偶极性质源于指向同一方向的两个 C-F 键的轴向取向，并由环己烷的椅式构象决定。这种静电分布在环的固态（X射线）堆积和不同溶剂中的溶液（NMR）中通过实验揭示。该化合物的计算得出的静电分布与环己烷环的电负性更强和正电性更强的面一致。这种将 CF2 基团 1,3 彼此放置在环己烷环中作为一种新的设计策略被引入，该策略可适用于极性疏水性环己烷基序的制备。
2,2-Dimethyl-5-phenyl-1,1,3,3-tetrafluororocyclohexane has been prepared and characterised as an example of a facially polarised cyclohexane containing 1,3 related CF2 groups. The dipolar nature of the ring arises from the axial orientation of two of the C–F bonds pointing in the same direction, and set by the chair conformation of the cyclohexane. This electrostatic profile is revealed experimentally both in the solid-state (X-ray) packing of the rings and by solution (NMR) in different solvents. A computationally derived electrostatic profile of this compound is consistent with a more electronegative and a more electropositive face of the cyclohexane ring. This placing of CF2 groups 1,3 to each other in a cyclohexane ring is introduced as a new design strategy which could be applicable to the preparation of polar hydrophobic cyclohexane motifs.