Question

- + Fit to page Page 1. Predict products of the reactions shown below, based on the trans effect (4) a. [PENCIT + NH, CN is the stronger tres director b. [PUNH:T" + c I) is the stronger trens director ra NH₃72 6) Pt 1 C N . Ci NH + NH3 CW + NR CI 2. Which of the following molecules shown below would have the shortest distance and explain your reasoning (3) - bond CHCO) CrCo in trans-CH(CO).ICCH) Cr CCH in Frans-CriCOCCH) 3. Which of the following molecules would have the lowest stretching frequency and explain your reasoning (3) Ni(CO (Coco [Fe(CO):12

Answer 1

2) The shorter Cr-C bond distance is lower for Cr -CO bond because CO is pi acceptor ligand and vacant pi antibindig is present for CO so there is possible of back bonding which increases Cr-CO bond order and decreases the distance

3) The last option which is [Fe (CO)4]2- is lowest stretching frequency because here Iron in -2 oxidation state and if electron density of central metal increases the back bonding increases so bond order between Cr-CO increases and Cr-CO stretching frequency decreases