Phosphane Nomenclature

The successive replacement of hydrogen in phosphine leads to primary phosphines, RPH2, secondary phosphines, R2PH and tertiary phosphines, R3P. 

The naming of simple acyclic phosphines is reasonably straightforward. They may be regarded as alkyl substituted phosphines or phosphine-substituted hydrocarbons, for example, 

Replacement of H by OH in primary and secondary phosphines leads to phosphonous, R P (0H)2, and phosphinous, R2POH acids, respectively. Such acids are, however, unstable in pyramidal form and undergo tautomeric changes to tetrahedral phosphinic acids and phosphine oxides. The relationship between pyramidal and tetrahedral forms can be expressed as equilibria (6.11-6.13). 

Names of trivalent and pentavalent acids end in ous and ic , respectively. The overlap of organic and inorganic nomenclature should be noted. Esters of phosphonous and phosphinous acids are named phosphonites, HP (0R)2 and phosphinites H2P (OR), respectively. 

Esters of phosphonic and phosphinic acids are named phosphonates, HP (O) (OR)2, and phosphi-nates, H2P (0)0R. Esters of phosphoric and phosphorous acids are named phosphates, P (O) (OR)3 and phosphites, P (OR)3, respectively. 

---

Also covered by this review are those compounds bearing two or three phosphane units at the same N atom, that is those derived from (H2P)2NH (N-phosphino phosphinous amide in CAS nomenclature) and from (H2P)3N, NJsl-bis(phosphino) phosphinous amide, but not those bearing more than one amino... 

In IUPAC nomenclature, a "phosphane" c normally a derivative of what wc ordinarily cal "phosphine. PH . PentavaJcnl derivatives of the liypethetkal PHj (phosphoranc) are Libeled X. Similarly, derivatives of H S would be ailfanes. and (he tctravalcnt and hexavakru derivatives would be labeled X4 and X6. respecuvdy. 

Suffixes and endings are of many different kinds (Table III), each of which conveys specific information. The following examples illustrate particular uses. They may specify the degree of unsaturation of a parent compound in substitutive nomenclature hexane, hexene and phosphane, diphosphene, diphosphyne. Other endings indicate the nature of the charge carried by the whole compound cobaltafe refers to an anion. Further suffixes can indicate that a name refers to a group, as in hexyl. 

In lUPAC nomenclature, a phosphane is normally a derivalive of whal we ordinarily call "phosphine." PH]. Penlavalenl derivatives of ihe hypollieiical PH, (phosphoianel are labeled h . Similarly, dcrivalives of H3S would be sulfanes. and Ihc tciravalciu and hcxavaknl derivalives would be labeled X nnd X". respectively. 

---