Proton Magnetic Resonance Analysis of Ring-substituted 2-Chloro-1,3,2-dioxaphosphorinanes.

Structural studies of phosphorinanes

“…Isomers of the chloro compounds 3^ (12), (12), 22 (13,14), 32 (12,19,20,28,30), 40 (9,22,23), although expected, have not been observed. Furthermore, pnmr spectra of the 2-chloro compounds ^ (9, 11), 2^ (9), 30 (29), and 41 (9) and to a greater extent those of the 2-bromo compounds 1^ (9) and £7 reversed for the b isomer as expected for equatorial and axial phosphoryl groups, respectively.…”

“…Analyses of nmr spectra of compounds 1^-3^ (8), 5 (9, 10), 7 (9, 10), 8 (11), n (9, 10, 11), 0^ (9, 10, 11), 13 (9, 10, 11), 15 (12), 1^ (12), ]^a (13,14), 18a,b (15), 19a,b (15,16), 21a (17), 22a,b (18), 23 (13,14), 26a,b (9, 10), 27a,b (9, 10), 37 (12,19,20), 38b (9,10,21,22), 42 (22), ^ (22), and ^ (9, 10, 11) have been accomplished by observation at one temperature only and all have been assigned a chair conforma tion, Spectra of compounds £ (9,10,11,23), £ (10,22), ^a,b (9,10,24), 25^a,b (9, 10), 28a,b (25), 32a (20), 33a (19,20), 34a (20), 35 (20), 38^a (9,10,21,22), ^ (9,10,21,22) and £1 (9,10) have been obtained at various tempera tures and concluded to exist in either a single rigid chair conformation or an equilibrium of two chair conformations indicated below for I and II which does not change appreciably within t...…”

“…2-Chloro-5,5-dimethyl-l,3,2-dioxaphosphorinane (12) This compound was prepared identically to ^ above from PClg and 2,2-dimethyl-!l,3-propandiol.…”

Structural studies of phosphorinanes

“…Edmundson and Mitchell (27) found that the two methyl groups at the C5 position of compound ^ differed in chemical shift and peak width at half height. They concluded that the broader, downfield methyl peak was due to axial methyl protons on the basis of unresolved residual coupling to the axial protons of C4 and C6 since these lie in a W configuration (13,14), 32 (12,19,20,28,30), 40 (9,22,23), although expected, have not been observed. Furthermore, pnmr spectra of the 2chloro compounds ^ (9, 11), 2^ (9), 30 (29), and 41 (9) and to a greater extent those of the 2-bromo compounds 1^ (9) and £7 and C6 axial protons in a versus b isomers.…”

“…Meso-2,4-pentanediol The slightly modified preparation of this compound originally reported by Pritchard and Vollmer (139) has been previously described (9). 2-Chloro-4,6-dimethyl-l,3,2-dioxaphosphorinane (40)The synthesis of this compound from PClg and meso-2,4pentanediol has been described previously (9).2-Chloro-4-methyl-l,3,2-dioxaphosphorinane C37)This compound was prepared identically to 4£ above from PClg and 1,3-butanediol.2-Chloro-5,5-dimethyl-l,3,2-dioxaphosphorinane(12) This compound was prepared identically to ^ above from PClg and 2,2-dimethyl-!l,3-propandiol.2-Chloro-l,3,2-dioxaphosphorinane(2) This compound was prepared identically to compound 40above from PCI^ and 1,3-propanediol.2-3-Methoxy-4,6-a,a-dimethyl-1,3,2-dioxaphosphorinane (38a)…”