Homotopic Faces hl

Reactions of hi and h4 are always avectoselective (ql,q2), with achiral or chiral reagents.  

Reactions of h2 and hs with achiral or chiral reagents are avectoselective (ql,q2), vectostereoselective (q6,q7,q8,q9), vectoastereoselective (ql3,q20) or vectononequiselective (ql4,ql6,21) h2, unlike hs, can display nonvectoselectivity (q3,q4), albeit with achiral reagents. 

In sum, (a) all homotopic faces hi-he can be avectoselective (achiral and chiral reagents) (b) only h2,hs can be nonvectoselective (achiral reagents) (c) only h2,h3,h5,he can be vectostereoselective (achiral and chiral reagents) (d) only h2 and hs can be vectoastereoselective as well as vectononequiselective (achiral and chiral reagents). It should be noted that a 

Q achiral conjunctive state chiral conjunctive state 

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An anguloselective process on a given homotopic face (hl-h3 of achiral substrates, and faces h4-h6 of chiral substrates) may occur with either an achiral or chiral reagent. 

Figure 14.17. Relationship of Facioselectivity, Vectoselectivity and Anguloselectivity for A2-Ligogenic Processes at Homotopic Faces hl-h2...

Facioselectivity, 2-79 classification of, 2-90 conjunctive states in, 2-81, 2-92 enantiotopic faces e, at 2-91 diastereotopic faces dl-d4, at 2-91 face-face conjunctive processes in, 2-97 homotopic faces hl-h6, at 2-91 stereofacioselectivity, 2-89 vectoselectivity, and 2-133 vectoselectivity-anguloselectivity, and 2-166... 

Table 17.1. Stereotopolysis/Stereotopomutation/Stereotopogenesis at Homotopic Faces hl-h6...

Tables 17.1-17.3 suiiunarize our findings about the relationship between the subclasses of stereotopoprocesses (stereotopolysis, stereotopomutation and stereotopogenesis), and, each of the different types of homotopic (hl-he), enantiotopic (e) and diastereotopic (dl-d4) faces.

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