Electrocyclic Reactions conrotatory disrotatory pericyclic reactions photochemical -thermal reaction

Assalam o Alaikum in this lecture i am going to discuss electrocyclic reaction with its types at photochemical and thermal conditions.An electrocyclic reaction is a pericyclic process in which a conjugated polyene undergoes cyclization. In the process, one π bond is converted into a σ bond, while the remaining π bonds all change their location. The newly formed σ bond joins the ends of the original π system, thereby creating a ring. Two examples are shown. Both reactions are reversible, but the position of equilibrium is different. The first example favors the cyclic product, while the second example disfavors formation of the cyclic product as a result of the ring strain associated with a four-membered ring. Note that the configuration of the product is dependent not only on the configuration of the reactant but also on the conditions of ring closure. That is, a different outcome is observed when the reaction is performed under thermal conditions (using heat) or under photochemical conditions (using UV light). The choice of whether to use thermal or photochemical conditions also has an impact on the stereochemical outcome of electrocyclic reactions with four π electrons. These stereochemical observations puzzled chemists for many years, until Woodward and Hoffmann developed their theory describing conservation of orbital symmetry. This single theory is capable of explaining all of the observations. We will first apply this theory to explain the stereochemical outcome of electrocyclic reactions taking place under thermal conditions, and then we will explore electrocyclic reactions taking place under photochemical conditions. Main contents that i have cover in this organic chemistry lecture are following:-\ 1) Electrocyclic Reactions and its types 2) photochemical and thermal Electrocyclic Reactions 3) electrocyclic reactions at photochemical condition 4) electrocyclic reactions at thermal condition 5) electrocyclic reactions at thermal condition for 6 or six pi electronic system 6) electrocyclic reactions at photochemical condition for 6 or six pi electronic system 7) electrocyclic reactions at thermal condition for 4 or four pi electronic system 8) electrocyclic reactions at photochemical condition for 4 or four pi electronic system 9)types of motion in electrocyclic reactions at thermal condition for 6 or six pi electronic system 10)types of motion in electrocyclic reactions at thermal condition for 4 or four pi electronic system 11)types of motion in electrocyclic reactions at photochemical condition for 4 or four pi electronic system 12)types of motion electrocyclic reactions at thermal condition for 4 or four pi electronic system 13) disrotatory motion in 6 or six pi electronic system at thermal condition 14) conrotatory motion in 4 or four pi electronic system at thermal condition 15)disrotatory in 4 or four pi electronic system at photochemical condition 16)conrotatory motion in 6 or six pi electronic system at photochemical condition 17)Stereochemistry of Thermal Electrocyclic Reactions in 4 or four pi electronic system at thermal condition 18)Stereochemistry of Thermal Electrocyclic Reactions in 6 or six pi electronic system at thermal condition 19)Stereochemistry of photochemical Electrocyclic Reactions in 6 or six pi electronic system at photochemical condition 20)Stereochemistry of photochemical Electrocyclic Reactions in 4 or four pi electronic system at photochemical condition. 21)what is the correct classification of pericyclic reaction, molecular orbital symmetry in pericyclic reactions,3 kinds of pericyclic reactions,pericyclic reactions and its types. 22)pericyclic reactions questions and answers, types of pericyclic reactions urdu lecture, 23) electrocyclic reaction explanation 24) electrocyclic reactions by authentic education channel ,FMO Approach PeriCyclic Reactions or electrocyclic reactions . 25)HOMO and LUMO concept according to MOT or FMOT and solved examples of pericyclic reactions. 26)conrotatory vs disrotatory & electrocyclic reactions practice problems & look at the following electrocyclic reaction & correlation diagram of electrocyclic reaction & conrotatory electrocyclization mechanism & electrocyclic reactions photochemical & conrotatory and disrotatory pdf. 27) what is a pericyclic reaction &fmo of 1,3,5 hexatriene & pericyclic reactions questions and answers & electrocyclic reactions ppt 28) electrocyclic reactions practice problems & fmo of 1,3,5 hexatriene symmetry of the HOMO involved in the reaction. excitation of an electron redefines the identity of the HOMO.