I. – COOH
II. – SH
III. – $CH_3$
IV. – CHO
Choose the correct answer from the codes given below :
Chelation is the process where a molecule binds to a central metal ion using two or more donor atoms, forming a ring structure. This ability depends on the presence of functional groups containing atoms with available lone pairs, such as Oxygen (O) or Sulfur (S), capable of coordinating with the metal ion.
Key Chelating Functional Groups Analysis
- Group I: $ - COOH $ (Carboxyl group): This group contains oxygen atoms. The deprotonated carboxylate form ($ - COO^- $) is an effective ligand that coordinates with metal ions, forming stable chelate rings.
- Group II: $ - SH $ (Thiol group): The sulfur atom in the thiol group possesses lone pair electrons and can readily coordinate with various metal ions, especially transition metals. Deprotonation to the thiolate ($ - S^- $) increases its coordinating ability.
- Group III: $ - CH_3 $ (Methyl group): This is a simple alkyl group. It lacks electronegative atoms with available lone pairs and does not have the capacity to coordinate with metal ions, thus it is not involved in chelation.
- Group IV: $ - CHO $ (Aldehyde group): The carbonyl oxygen atom ($ C=O $) in the aldehyde group can participate in coordination with metal ions, contributing to the chelation process.
Based on this analysis, functional groups I ($ - COOH $), II ($ - SH $), and IV ($ - CHO $) possess the necessary coordinating atoms (O and S) required for effective chelation of metal ions. Group III ($ - CH_3 $) does not.
Important Questions from Bioinorganic Chemistry
Consider the following transformation reactions in the context of co - enzyme B12
A. 1, 2 - Carbon shift
B. Hydration of CO2
C. Benzene to phenol
D. Dimethyl sulfide to dimethyl sulfoxide
The correct statement(s) for co - enzyme B12 is / are
During the binding of O2 to myoglobin (consider 'heme' in xy-plane), the molecular orbital of O2 and atomic orbital of Fe involved in the formation of the σ-bond is
In the catalytic cycle of Cytochrome P450, the generation of [(porphyrin)+•FeIV(O)] from [(porphyrin)FeIII(OOH)] involves
Match List I with List II
List I
List II
Metalloprotein
Metal
A.
carboxypeptidase A
I.
Mn
B.
oxygen-evolving complex
II.
Fe
C.
hemerythrin
III.
Ni
D.
coenzyme F-430
IV.
Zn
Choose the correct answer from the options given below:
In solution, Vaska's complex is known to bind O2 reversibly. In the product, oxidation state of the metal ion center coordination geometry and mode of binding of O2, respectively are
