1 / 72

Principals of Organic Chemistry مبادئ الكيمياء العضوية CHEM 230

Principals of Organic Chemistry مبادئ الكيمياء العضوية CHEM 230. معلومات عن أستاذة المقرر. الاسم : د. سوزان عبدالرحمن خياط أستاذ الكيمياء العضوية المشارك قسم الكيمياء كلية العلوم (فرع الفيصلية) – جامعة الملك عبدالعزيز غرفة رقم 314 A الدور الثاني – 109 C الدور الأرضي

tswenson
Download Presentation

Principals of Organic Chemistry مبادئ الكيمياء العضوية CHEM 230

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Principals of Organic Chemistry مبادئ الكيمياء العضوية CHEM 230

  2. معلومات عن أستاذة المقرر • الاسم : د. سوزان عبدالرحمن خياط • أستاذ الكيمياء العضوية المشارك • قسم الكيمياء • كلية العلوم (فرع الفيصلية) – جامعة الملك عبدالعزيز • غرفة رقم 314A الدور الثاني – 109 C الدور الأرضي • البريد الإلكتروني suzan122@hotmail.com saekhayyat@kau.edu.sa • الموقع الإلكتروني www.saekhayyat.kau.edu.sa

  3. أهداف المقرر: يهدف المقرر إلى تعميق فهم الطالبة عن الترابط الكيميائي، تصنيف المركبات العضوية وتسميتها، والتشكل بأنواعه في المركبات العضوية، ودراسة التفاعلات العضوية الهامه لأصناف المركبات العضوية المختلفة. المحتوى العلمي للمقرر: دراسة الربط الكيميائي في المركبات العضوية من خلال نظرية التهجين - تقسيم المركبات العضوية حسب المجموعة الوظيفية - تسمية المركبات العضوية - التشكل - التفاعلات الكيميائية - المركبات الحلقية غير المتجانسة – السكريات - الأحماض الأمينية والبروتينات - التربينات -تطبيقات المركبات العضوية في الطب والزراعة والتغذية والصناعة chapter 1

  4. توزيع الدرجات chapter 1

  5. Main Text Book الكتاب الرئيسي المقرر “Organic Chemistry”, T. W. ,Graham Solomons & Caring B. Fryhle; 8th ed, 2007. chapter 1

  6. Chapter 1BCarbon Compounds and Chemical Bonds chapter 1

  7. Organic compounds are compounds that could be obtained from living organisms. Inorganic compounds are compounds that came from nonliving sources.

  8. Introduction of Organic Chemistry • The chemistry of the compounds of carbon. • The human body is largely composed of organic compounds. • Organic chemistry plays a central role in medicine, bioengineering etc.

  9. Common Elements in Organic Compounds

  10. The structure of atom Simplified structure of an atom structure of carbon atom

  11. Chemical Bonds: The Octet Rule Octet Rule • Atoms form bonds to produce the electron configuration of a noble gas (because the electronic configuration of noble gases is particularly stable). • For most atoms of interest this means achieving a valence shell configuration of 8 electrons corresponding to that of the nearest noble gas. • Atoms close to helium achieve a valence shell configuration of 2 electrons. • Atoms can form either ionic or covalent bonds to satisfy the octet rule. G. N. Lewis

  12. A chemical bond is a force of attraction that holds two atoms together to fill its electron shells with 8 electrons (octet rule). Kinds of chemical bonds: • Ionic bonds • Covalent bonds • Metallic bonds chapter 1

  13. IONIC BONDbond formed between two ions by the transfer of electrons

  14. The Covalent Bond A covalent bondis a chemical bond formed between (nonmetal + nonmetal) or (metalloide + nonmetal) in which two or more electrons are shared by two atoms. chapter 1

  15. The Covalent Bond • Covalent bonds occur between atoms of similar electronegativity(close to each other in the periodic table) • Atoms achieve octets by sharing of valence electrons • Molecules result from this covalent bonding • Valence electrons can be indicated by dots (electron-dot formula or Lewis structures) but t time-consuming • The usual way to indicate the two electrons in a bond is to use a line (one line = two electrons) chapter 1

  16. The Covalent Bond Oxygen Atom Oxygen Atom Oxygen Molecule (O2) chapter 1

  17. The Covalent Bond when two atoms share a pair of electrons. P+1 P+1 chapter 1

  18. The Covalent Bond when two atoms share a pair of electrons. P+1 P+1 It’s like both atoms have a filled orbital. chapter 1

  19. The Covalent Bond The sharing of a pair of electrons between 2 atoms. (or even 2 or 3 pairs of electrons). H2

  20. The Covalent Bond The sharing of a pair of electrons between 2 atoms. Cl2

  21. Covalent Bonds • Non polar covalent Bond • Atoms achieve octets by sharing of valence electrons • Molecules result from this covalent bonding • Valence electrons can be indicated by dots (electron-dot formula or Lewis structures) but this is time-consuming • The usual way to indicate the two electrons in a bond is to use a line (one line = two electrons) Chapter 1

  22. F H F H 2-Polar covalent bond or polar bond is a covalent bond with greater electron density around one of the two atoms electron rich region electron poor region e- poor e- rich d+ d- 9.5

  23. Orbital: a region in space where the probability of finding an electron is large • Atomic Orbitals (AOs): The region of space where one or two electrons of an isolated atom are likely to be found. • Molecular Orbitals (MOs) :The region of space where one or two electrons of a molecule are likely to be found. chapter 1

  24. Bonding Molecular Orbitals (Ymolec) • AOs combine by addition (the AOs of the same phase sign overlap) • The value of Y2 (electron probability density) in the region between the two nuclei increases • The two electrons between the nuclei serve to attract the nuclei towards each other • This is the ground state (lowest energy state) of the MO chapter 1

  25. Molecular Orbital of Hydrogen antibonding orbital bonding orbital chapter 1

  26. The energy of electrons in the bonding orbitals is substantially less than the energy of electrons in the individual atoms • The energy of electrons in the antibonding orbitals is substantially more • In the ground state of the hydrogen molecule electrons occupy the lower energy bonding orbital only chapter 1

  27. Bonding Molecular Orbital The overlapping of two hydrogen 1satomic orbitals 1s 1s Ø1 atomic orbital Ø2 atomic orbital Ψ+ = Ø1 + Ø2 bonding orbital The overlapping of two hydrogen 1swaves chapter 1

  28. Antibonding molecular orbital (Y *molec) • Formed by interaction of AOs with opposite phase signs • Electrons in the antibonding orbital avoid the region between the two nuclei • Repulsive forces between the nuclei predominate and electrons in antibonding orbitals make nuclei fly apart chapter 1

  29. Antibonding Molecular Orbital The overlapping of two hydrogen 1satomic orbitals 1s 1s Ψ- = Ø1 - Ø2 antibonding orbital Ø1 atomic orbital Ø2 atomic orbital The overlapping of two hydrogen 1swaves node chapter 1

  30. Formation of (sigma σ)bond H2 HCl Cl2 chapter 1

  31. a) Sigma bond formation by s – s overlap Diagram of sigma bond formation by s – s overlap chapter 1

  32. b) Sigma bond formation by s – p overlap Diagram of sigma bond formation by s – p overlap chapter 1

  33. c) Sigma bond formation by p – p overlap Energy Diagram of sigma bond formation by p – p overlap chapter 1

  34. Formation of (pi π)bond chapter 1

  35. Structural Theory Central Premises • Valency: atoms in organic compounds form a fixed number of bonds. • Carbon can form one or more bonds to other carbons.

  36. The Structure of Methane and Ethane: sp3 Hybridization • The structure of methane with its four identical tetrahedral bonds cannot be adequately explained using the electronic configuration of carbon • Hybridization of the valence orbitals (2s and 2p) provides four new identical orbitals which can be used for the bonding in methane • Orbital hybridization is a mathematical combination of the 2s and 2p wave functions to obtain wave functions for the new orbitals chapter 1

  37. When one 2s orbital and three 2p orbitals are hybridized four new and identical sp3 orbitals are obtained • When four orbitals are hybridized, four orbitals must result • Each new orbital has one part s character and 3 parts p character • The four identical orbitals are oriented in a tetrahedral arrangements • The antibonding orbitals are not derived in the following diagram • The four sp3 orbitals are then combined with the 1s orbitals of four hydrogens to give the molecular orbitals of methane • Each new molecular orbital can accommodate 2 electrons chapter 1

  38. sp3 hybridization in Methane CH4 excitation becomes Ground state excited state chapter 1

  39. chapter 1

  40. A variety of representations of methane show its tetrahedral nature and electron distribution • a. calculated electron density surface b. ball-and-stick model c. a typical 3-dimensional drawing chapter 1

  41. Molecule geometry of CH4 4 sp3 hybrid orbitals 10.4

  42. Ethane (C2H6) • The carbon-carbon bond is made from overlap of two sp3 orbitals to form a s bond • The molecule is approximately tetrahedral around each carbon chapter 1

  43. The representations of ethane show the tetrahedral arrangement around each carbon • a. calculated electron density surface b. ball-and-stick model c. typical 3-dimensional drawing Generally there is relatively free rotation about s bonds • Very little energy (13-26 kcal/mol) is required to rotate around the carbon-carbon bond of ethane chapter 1

  44. Examples of Sigma Bond Formation

  45. The Structure of Ethene (Ethylene) : sp2Hybridization • Ethene (C2H2) contains a carbon-carbon double bond and is in the class of organic compounds called alkenes • Another example of the alkenes is propene • The geometry around each carbon is called trigonal planar • All atoms directly connected to each carbon are in a plane • The bonds point towards the corners of a regular triangle • The bond angle are approximately 120o chapter 1

  46. The C—C s Bond in Ethane In-phase overlap of half-filled sp3 hybridorbital of one carbon with half-filled sp3hybrid orbital of another. Overlap is along internuclear axis to give a s bond.

  47. The C—C s Bond in Ethane In-phase overlap of half-filled sp3 hybridorbital of one carbon with half-filled sp3hybrid orbital of another. Overlap is along internuclear axis to give a s bond.

  48. hybrid orbitals – sp, sp2, or sp3

  49. hybrid orbitals – sp, sp2, or sp3

More Related