Alkyne

The purpose of this two-part experiment was to convert an alkene to alkyne. This is difficult to accomplish in one step, thus a multi-step process was used to produce the alkyne. First, bromination of stilbene through the electrophilic addition of bromine to the double bond was performed through an SN2 reaction, as outlined in Figure 3. Pyridinium tribromide, the source of bromine, since elemental bromine is too corrosive and hazardous, was generated in situ (Figure 1). The bromine was added across the double bond and attacked through the backside, anti-relative to the other bromide. This mechanism produced meso-1,2-dibromo-1,2-diphenylethane as the sole products. Although, cis-1,2-dibromo-1,2-diphenylethane can be generated the substituent groups are too sterically hindered and the molecule too unstable to be a viable product in this reaction (Figure 2). This is evident in the notably different melting points of the isomers, cis-1,2-dibromo-1,2-diphenylethane has a melting point of 113°C while the melting point of meso-1,2-dibromo-1,2-diphenylethane is about 238°C (University of Windsor, 2015). Figure 1: Pyridinium tribromide generated in situ Figure 2: Isomers of 1,2-dibromo-1,2-diphenylethane vicinal dibromide Figure 3: Bromination Reaction Mechanism trans-stilbene 
 vicinal dibromide…

Introduction A reaction in organic chemistry that involves a simultaneous 3 pi bond shift is Diels-Alder cycloaddition, where a conjugated diene and an alkene with an electron withdrawing group (a dienophile) will react to form two carbon-carbon single bonds at the expense of the one carbon-carbon multiple bond to most often form a 6 membered ring adduct (Ketcha, 106). A conjugated diene is a hydrocarbon the contains two carbon-carbon double bonds and a dienophile also means “diene-loving”…

Dehydrobromination of meso-Stilbene Dibromide Introduction This procedure was performed in order to synthesize an alkyne from meso-stilbene dibromide through double dehydrohalogenation. The removal of the two bromine and two hydrogen atoms allows for the formation of the carbon triple bond and thus the formation of an alkyne. The alkyne formed is diphenylacetylene. Data and Results The melting point of the product was measured to be between 60C and 62C. The actual melting point of…

Even though there are multiple medications available over-the-counter or by prescriptions, researchers are constantly trying to develop antidotes to numerous illnesses in today’s society. Current research developments are extremely extortionate or lengthy when no significant results are accumulated. Therefore in my research, cost-effective methodology is used in trials to synthesize organic complexes. Organic complexes, such as vinylketenes and cyclooctynes are highly reactive reagents, and if…

The different types of alkanes used will be pentane (C5H12), hexane (C6H14), heptane (C7H16) and octane (C8H18). They will be mixed with the alcohol pentanol (C5H12O). The formula used to calculate the heat is Q=mcΔT. When measuring the heat of mixtures it is different as two different percentages of substances are being measured. The formula used to calculate it is still Q=mcΔT. Organic chemistry is the scientific study of the structure, properties, and reactions of organic compounds and…

The sequence of the reactions employed for the construction of novel indole–benzimidazole-based 1,2,3-triazole hybrids is demonstrated in Scheme 1. Compound 2 was prepared by treating propargyl bromide with 1H-indole-3-carbaldehyde (1) in presence of potassium carbonate in dry acetone at reflux temperature [26]. Compound 2 was further reacted by heating at reflux temperature with o-phenylenediamine (OPDA) in chloroform for 6 h afforded compound 3. Compound 3 coupled with variously substituted…

C-H stretch Alkanes and acids 7 2912.38 0.2040 Medium C-H stretch Alkanes 8 2834.49 0.3170 Weak C-H stretch Aldehydes and acids 9 2524.07 0.0337 Medium O-H stretch Carboxylic acids 10 2226.40 0.0033 Weak C ≡C stretch Alkynes 11 2043.60 0.0059 Unknown 12 1785.35 0.0104 Unknown 13 1659.54 0.0303 Medium C =C stretch Amides and alkenes 14 1477.37 0.0519 Medium C-C stretch Aromatic…

investigate how the length of carbon chains affect the heat of combustion and enthalpy, in order to determine which fuel would be the safest and most efficient to take on a camping trip. HYPOTHESIS If the number of carbon atoms in an alkanol is increased, then the alkanol containing the longest carbon chain will have a higher heat of combustion, because as there are more carbon atoms, more energy will be released as a result of the breaking of the covalent bonding and the forming of bonding…

Comparison of Organometallic Compounds of Transition Metals and Main Group Elements Organometallic Compounds: The compounds which contain at least one direct metal to carbon covalent bond are known as organometallic compounds many of these are thermodynamically unstable and are pyrophoric. The meta may belongs to main group, transition metal, f group metal or a metalloid i.e. selenium, boron, arsenic, silicon, antimony, germanium, and tellurium and the carbon moiety may be alkyl, alkene, alkyne,…

Experiment 1: Alkanes & alkenes: Combustion and action of sulphuric acid. Objective: To make careful observations and compare the difference(s) between alkanes and alkenes. Introduction: Hydrocarbons are composed exclusively of oxygen and hydrogen. There are three types of homogeneous hydrocarbons (whose members differ by one CH2 unit): alkanes, alkenes and alkynes. The difference between these three groups is in the bond types between the carbons. Alkanes form only single bonds, alkenes…