UNIVERSITI MALAYA UNIVERSITY F MALAYA PEPERIKSAAN IJAZA SARJANA MUDA SAINS EXAMINATIN FR TE DEGREE F BACELR F SCIENCE PEPERIKSAAN IJAZA SARJANA MUDA SAINS DENGAN PENDIDIKAN EXAMINATIN FR TE DEGREE F BACELR F SCIENCE WIT EDUCATIN SESI AKADEMIK 2009/2010 : SEMESTER 2 ACADEMIC SESSIN 2009/2010 : SEMESTER 2 SCES1220/SCEP1220 : KIMIA RGANIK I RGANIC CEMISTRY I April/Mei 2010 April/May 2010 MASA : 2 jam TIME : 2 hours ARAAN KEPADA CALN : INSTRUCTINS T CANDIDATES : Jawab SEMUA EMPAT (4) soalan. Answer ALL FUR (4) questions. (Kertas ini mengandungi 4 soalan dalam 8 halaman yang dicetak) (This question paper consists of 4 questions on 8 printed pages)
SCES1220/SCEP1220/02 1.(a) Lukis struktur yang memenuhi setiap kenyataan berikut. Draw structure(s) that satisfies (satisfy) each of the following statement. Formula unjuran Newman konformasi paling stabil apabila bromokloroetana diputarkan pada ikatan C C. Newman projection formula of the most stable conformation when bromochloroethane is rotated about the C C bond. Struktur resonans untuk ion (I). Resonance structure(s) for ion (I). (I) + Konformer kerusi paling stabil bagi 1-t-butil-4-etil-2-metilsikloheksana. The most stable chair conformation of 1-t-butyl-4-ethyl-2-methylcyclohexane. (iv) Karbokation paling stabil yang terbentuk apabila sebatian (II) diolahkan dengan +. The most stable carbocation formed when compound (II) is treated with +. (II) C 2 (v) asil utama yang terbentuk apabila 3-metilpentana ditindak balaskan dengan Br 2 dalam kehadiran cahaya. The major product formed when 3-methylpentane is reacted with Br 2 in the presence of light. (vi) asil yang terbentuk apabila alkuna (III) diolahkan dengan 3 dan diikuti oleh 2. The product(s) formed when alkyne (III) is treated with 3 followed by 2. C C C 2 C 2 C C (III) (10 markah/ marks)
SCES1220/SCEP1220/03 (b) Pertimbangkan tindak balas berikut. asil manakah dijangkakan merupakan sama ada satu-satunya hasil atau hasil utama yang terbentuk Jelaskan jawapan anda dengan menulis mekanisme tindak balas lengkap. Consider the following reactions. Which compound is expected to be either the only product or the major product formed Justify your answers by writing complete reaction mechanisms. 1. C 2 2. 2, + atau or atau or CC 2, F C 2 C atau or CC 2 (10 markah/ marks) (c) Pertimbangkan tindak balas 2-metilbutena dengan reagen Wijs, suatu larutan iodin monoklorida, I. Tulis mekanisme untuk penambahan I pada 2- metilbutena, bincangkan stereokimia tindak balas dan tentukan hasil utama yang terbentuk. Consider the reaction of 2-methylbutene with Wijs reagent, a solution of iodine monochloride, I. Write the mechanism for the addition of I to 2-methylbutene, discuss the stereochemistry of the reaction and determine the major product formed. C 2 C C 2 I (5 markah/ marks)
SCES1220/SCEP1220/04 2.(a) Tulis mekanisme lengkap bagi menjelaskan hasil yang terbentuk dalam setiap tindak balas berikut. Write complete mechanism to illustrate the product(s) formed in each of the following reactions. C 2 S 4 + Br + Br 2 + Br C 2 C C, Br C 2 C Br (15 markah/ marks) (b) Beri hasil utama, bahan pemula atau reagen untuk tindak balas berikut. Di mana berkenaan, tunjukkan stereokimia bahan pemula atau hasil. Give the major product(s), starting material(s) or reagent(s) for the following reactions. Where appropriate, indicate the stereochemistry of the starting material(s) or product(s). + Br 2 h 1. C 2. 2, + Br
SCES1220/SCEP1220/05 (iv) (v) + C 2 KMn 4, - (vi) 100oC (vii) S 3, 2 S 4 C ( + isomer ) (10 markah/ marks) 3.(a) Lukis kedua-dua konformasi kerusi terbitan sikloheksana berikut. Konformer manakah lebih stabil Jelaskan jawapan anda. Draw both chair conformations of the following cyclohexane derivative. Which conformer is more stable ffer an explanation for your answer. (5 markah/ marks)
SCES1220/SCEP1220/06 (b) Beri penjelasan bagi pemerhatian berikut. Tulis mekanisme munasabah di mana berkenaan. ffer explanations for the following observations. Write plausible mechanisms where appropriate. Konformer gauche etana-1,2-diol, C 2 C 2, lebih stabil daripada konformer anti. The gauche conformer of ethane-1,2- diol, C 2 C 2, is more stable than the anti conformer. Alkohol (A) lebih cepat mengalami pendehidratan bermangkinkan asid berbanding alkohol (B). Alcohol (A) undergoes acid-catalyzed dehydration faster than alcohol (B). (A ) (B ) Pengolahan p-bromotoluena dengan natrium amida dalam ammonia cecair menghasilkan campuran p-metilanilina dan m-metilanilina. Treatment of p-bromotoluene with sodium amide in liquid ammonia gives a mixture of p-methylaniline and m-methylaniline. (15 markah/ marks) (c) Kelaskan setiap spesis berikut sebagai aromatik, antiaromatik atau bukan aromatik. Jelaskan jawapan anda. assify each of the following species as aromatic, antiaromatic or non-aromatic. Justify your answers. + (iv) (v) (5 markah/ marks)
SCES1220/SCEP1220/07 4.(a) Tunjukkan bagaimana LIMA (5) daripada penukaran berikut dapat dilakukan. Tulis semua reagen yang digunakan dan perantaraan yang terlibat. Show how FIVE (5) of the following transformations can be carried out. Write all reagents used and intermediates involved. CC 2 I C C C 2 C C C C 2 (iv) C C C 2 (v) N 2 C 2 C 2 (vi) (20 markah/ marks)
SCES1220/SCEP1220/08 (b) Lukis struktur stereoisomer yang terbentuk dalam tindak balas berikut. Write the structure(s) of the stereoisomer(s) formed in the following reactions. Br 1. g( C ) 2, 2 2. NaB 4, - + CC 2 Al 3 (5 markah/ marks) ~~~~~0000~~~~~