In the following reaction, ' $A$ ' is
In the following reaction, ' $A$ ' is
Show Hint
Carbamates (R-NH-C(=O)OR’) are commonly formed by the reaction of primary amines with chloroformates (RO-C(=O)-Cl).
The Correct Option is A
Approach Solution - 1
Analysis of the Given Reaction:
The given reaction involves a substitution of the hydroxyl group (-OH) with an ethyl carbamate (-COOEt) group to form the major product. The steps are as follows:
- The compound NH2−CH2OH reacts with ethyl chloroformate (EtO-C(=O)-Cl) under basic or catalytic conditions.
- The primary amine group (−NH2) undergoes nucleophilic attack on the carbonyl carbon of ethyl chloroformate, resulting in the formation of a carbamate group (NH-C(=O)OEt).
The major product, A, is NH-C(=O)OEt, as shown in option (1).
Approach Solution -2
The correct answer is option (A) : 
Initially lone pair electrons of −NH2 attack electrophilic carbon, after then lone pair electrons of oxygen attack leading to the formation of a cyclic compound.
Top JEE Main Chemistry Questions
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- At equilibrium the concentrations of and in a sealed vessel at . What will be for the reaction
- Find out the major products from the following reactions
Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
- The correct order of atomic radii is:
Top JEE Main Chemical Reactions Questions
- The products A and B formed in the following reaction scheme are respectively
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: H2Te is more acidic than H2S.
Reason R: Bond dissociation enthalpy of H2Te is lower than H2S.
In light of the above statements, choose the most appropriate from the options given below:
- Which of the following reactions are disproportionation reactions?
\(\text{(A) } \text{Cu}^+ \rightarrow \text{Cu}^{2+} + \text{Cu}\)
\(\text{(B) } 3\text{MnO}_4^{2-} + 4\text{H}^+ \rightarrow 2\text{MnO}_4^- + \text{MnO}_2 + 2\text{H}_2\text{O}\)
\(\text{(C) } 2\text{KMnO}_4 \rightarrow \text{K}_2\text{MnO}_4 + \text{MnO}_2 + \text{O}_2\)
\(\text{(D) } 2\text{MnO}_4^- + 3\text{Mn}^{2+} + 2\text{H}_2\text{O} \rightarrow 5\text{MnO}_2 + 4\text{H}^+\)
Choose the correct answer from the options given below. - Products for the below reaction are:
- Major product of the following reaction is
Top JEE Main Questions
- In a hydrogen like atom, when an electron jumps from the $M$ - shell to the $L$ - shell, the wavelength of emitted radiation is $\lambda$. If an electron jumps from $N$-shell to the $L$-shell, the wavelength of emitted radiation will be :
- Two masses $m$ and $\frac{m}{2}$ are connected at the two ends of a massless rigid rod of length $l$. The rod is suspended by a thin wire of torsional constant $k$ at the centre of mass of the rod-mass system(see figure). Because of torsional constant $k$, the restoring torque is $\tau =k\theta$ for angular displacement $\theta$. If the rod is rota ted by $\theta_0$ and released, the tension in it when it passes through its mean position will be:
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- The value of is
- The number of terms of an is even. The sum of the odd terms is and of the even terms is . The last term exceeds the first by . Then the number of terms in the series is ______.
Concepts Used:
Laws of Chemical Combination
Basic Laws of Chemical Combinations:
The five basic laws of chemical combination for elements and compounds are given below.
Law of Conservation of Mass:
The Law of conservation of mass or the principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so the quantity can neither be added nor be removed.
Law of Definite Proportions:
The Law of definite proportions, sometimes called Proust's law, or the law of constant composition states that a given chemical compound always contains its component elements in a fixed ratio and does not depend on its source and method of preparation
Law of Multiple proportions:
The Law of multiple proportions states that if two elements form more than one compound, then the ratios of the masses of the second element which combine with a fixed mass of the first element will always be ratios of small whole numbers.
Gay Lussac’s Law of Gaseous Volumes:
Gay Lusaacc's law of gaseous volume states that the pressure of a given mass of gas varies directly with the absolute temperature when the volume is kept constant.
Avogadro’s Law:
Avogadro-Ampère's hypothesis is an experimental gas law relating the volume of a gas to the amount of substance of gas present.