Apicophilicity and Ring-Strain in Five-Coordinate Phosphoranes

Synthesis, structure, and reaction of tricoordinate stibine and tetracoordinate stiboranide

“…The relative preference of substituent occupying the apical site is particularly known as apicophilicity [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. From many experimental systems and theoretical calculations, an oxygen atom is determined to be much more apicophilic than a carbon atom [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. Antiapicophilic compound, which violates relative apicophilicity of the elements, generally has high energy and is unstable, thus easily isomerizes into its stable apicophilic compound.…”

Control of Phosphoryl Migratory Transesterifications Allows Regioselecive Access to Sugar Phosphates

“…The protocol we describe allows control of regiochemistry during phosphoryl migrations, which occur via a cyclic intermediate 13 with outcome dictated by a pentacoordinate P centre (Scheme 6). 19 A kinetic preference for migration to OH-4 (cf Scheme 4, Entry 14), observed previously, 20,21 can be explained by apicophilicity of the most electronegative, primary OH-6 in 11 (see SI for discussion); 20,22,23 extrusion of the longer P-O(6) bond would be more facile giving 9. However, sterics may override electronics.…”

“…However, sterics may override electronics. 22 Fions interact strongly with hydroxyls 24 and create H-bonding networks within solvent 25 (described as "structure markers" that increase solvent ordering 26 ) particularly in methanolic solutions of CsF. 27,28…”

Sulfurization of Trivalent Phosphorus Compounds with 1,2-Dithiole-3-thione

“…Such a structure should be the most convenient from the point of view of apicophilicity of substituents at phosphorus in trigonal-bipyramidal species. 15 Decomposition of the fivecoordinate intermediate 18 gives the phosphine sulfide with retention of configuration at phosphorus and the carbene intermediate 19 from which polymer 20 could possibly be formed. 8 This proposal is in full agreement with the experimental observation that a black polymeric precipitate was always formed during the discussed thionation reaction.…”