310_16 - Organic Lecture Series CH 310 N LECTURE 16...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Organic Lecture Series 1 CH 310 N LECTURE 16 Textbook Assignment: Chapter 20 Conjugated systems Homework (for credit): Problem Set – None this week Today’s Topics: Dienes & Conjugation (OMIT 20.3) Notice & Announcements: EXAM 2: Grading in Progress Organic Lecture Series 2 Conjugated Conjugated Systems Systems (Omit 20.3) (Omit 20.3)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Organic Lecture Series 3 from heats of hydrogenation-relative stabilities of conjugated vs unconjugated dienes can be studied: Δ H 0 -237 (-56.5) 1,3-Butadiene -126 (-30.1) -127 (-30.3) kJ (kcal)/mol Name 1-Pentene 1-Butene trans- 1,3-Pentadiene 1,4-Pentadiene 2-Butene -115 (-27.6) cis- 2-Butene -120 (-28.6) -226 (-54.1) -254 (-60.8) Structural Formula Conjugated Conjugated Dienes Dienes conjugated Organic Lecture Series 4 conjugation of the double bonds in 1,3-butadiene gives an extra stability of approximately 17 kJ (4.1 kcal)/mol 2H 2 + catalyst Δ H 0 = 2(-127 kJ/mol) = -254 kJ/mol) 22 2 + Δ H 0 = -237 kJ/mol catalyst Conjugated Conjugated Dienes Dienes
Background image of page 2
Organic Lecture Series 5 Conjugated Conjugated Dienes Dienes C C C C H 2 C H C H C CH 2 The π systems of the 2 olefins overlap S-cis conformer Organic Lecture Series 6 C C C C H 2 C H C C H CH 2 S-Trans conformer Conjugated Conjugated Dienes Dienes
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Organic Lecture Series 7 – systems containing conjugated double bonds, not just those of dienes, are more stable than those containing unconjugated double bonds 3-Cyclohexenone
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 11/21/2011 for the course CH 51455 taught by Professor Colapret during the Spring '11 term at University of Texas at Austin.

Page1 / 11

310_16 - Organic Lecture Series CH 310 N LECTURE 16...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online