2-Phosphanyl-substituted imidazolium salts 2-PR₂(4,5-Cl-Im)[OTf] (9a,b[OTf]) (4,5-Cl-Im = 4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolium) (a: R = Cy, b: R = Ph) are prepared from the reaction of R₂PCl (R = Cy, Ph) with NHC 8 (4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolin-2-ylidene) in the presence of Me₃SiOTf. 5-Phospanyl-substituted imidazolium salts 5-PR₂(2,4-Cl-Im)[OTf] (10a,b[OTf]) are obtained in quantitative yield when a slight excess of the NHC 8 is used. 5-Phosphonio-substituted imidazolium salts 5-PR₂Me(2,4-Cl-Im)[OTf]₂ (14a,b[OTf]₂) and 5-PR₂F(2,4-Cl-Im)[OTf]₂ (16a,b[OTf]₂) result from methylation reaction or oxidation of 10a,b[OTf] with XeF₂ and subsequent fluoride abstraction. According to our quantum chemical studies the Cl1 atom at the 2-position at the imidazolium ring of dication 14b²⁺ carries a slightly positive charge and is therefore accessible for nucleophilic attack. Accordingly, the reaction of 14a,b[OTf]₂ and 16a,b[OTf]₂ with R₃P (R = Cy, Ph) affords cationic 5-phosphonio-substituted NHCs 5-PR₂Me(4-Cl-NHC)[OTf] (17a,b[OTf]) and 5-PR₂F(4-Cl-NHC)[OTf] (18a,b[OTf]) via a S_N2(Cl)-type reaction. A series of transition metal complexes such as [AuCl(5-PPh₂Me(4-Cl-NHC))][OTf] (19[OTf]), [CuBr(5-PPh₂Me(4-Cl-NHC))][OTf] (20[OTf]), [AuCl(5-PPh₂F(4-Cl-NHC))[OTf] (21[OTf]) and [RhCl(cod)(5-PPh₂Me(4-Cl-NHC))][OTf] (23[OTf]) are prepared to prove the coordination abilities of carbenes 17b[OTf] and 18b[OTf]. The isolation of a rare example of a tricationic bis-carbene silver complex [Ag(5-PPh₂Me(4-Cl-NHC))₂][OTf]₃ (22[OTf]₃) is achieved by reacting 14b[OTf] with Cy₃P in the presence of AgOTf. NHC 17b[OTf] represents a very effective dehydrocoupling reagent for secondary (R₂PH, R = Ph, Cy, ⁱBu) and primary (RPH₂, R = Ph, Cy) phosphanes to give diphosphanes of type R₄P₂ (R = Ph, Cy, ⁱBu) and oligophosphanes R₄P₄, R₅P₅ (R = Ph, Cy), respectively. Methylation of 17b⁺ and subsequent deprotonation reaction with LDA affords the cationic NHO (N-heterocyclic olefin) 35⁺ of which the gold complex 36⁺ is readily accessible via the reaction with AuCl(tht).